Toyota Avalon (XX50): Adaptive Variable Suspension System

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Suspension / Suspension Control / Adaptive Variable Suspension System

Front Acceleration Sensor RH Malfunction (C1715-C1717,C1796-C1798)

DESCRIPTION

The acceleration sensor (up and down G sensor) detects the upward and downward acceleration of the vehicle and outputs it as a voltage to the absorber control ECU.

The 3 up and down G sensors are installed in the driver side instrument panel, the passenger side instrument panel and the absorber control ECU.

Each up and down G sensor independently detects the upward and downward acceleration of the vehicle.

During a test mode inspection, the absorber control ECU reads the fluctuations in each sensor signal.

When a sensor signal does not fluctuate, test mode DTCs C1796, C1797 and C1798 remain stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

C1715

Front Acceleration Sensor RH Malfunction

One of the following conditions is met:

  • With the engine switch on (IG), a voltage of 5.5 V or more, or 4.3 V or less is detected at the power source of the acceleration sensor assembly RH for 0.5 seconds.
  • With the engine switch on (IG), a voltage of 4.7 V or more, or 0.3 V or less is detected at the acceleration sensor assembly RH for 1 second.
  • Sensor output value is +/- 0.0639 m/s2 continuously for 300 seconds.
  • Acceleration sensor assembly RH
  • Wire harness or connector
  • Absorber control ECU

Does not come on

Yes

C1716

Front Acceleration Sensor LH Malfunction

One of the following conditions is met:

  • With the engine switch on (IG), a voltage of 5.5 V or more, or 4.3 V or less is detected at the power source of the acceleration sensor assembly LH for 0.5 seconds.
  • With the engine switch on (IG), a voltage of 4.7 V or more, or 0.3 V or less is detected at the acceleration sensor assembly LH for 1 second.
  • Sensor output value is +/- 0.0639 m/s2 continuously for 300 seconds.
  • Acceleration sensor assembly LH
  • Wire harness or connector
  • Absorber control ECU

Does not come on

Yes

C1717

Rear Acceleration Sensor Malfunction

One of the following conditions is met:

  • With the engine switch on (IG), a voltage of 5.5 V or more, or 4.3 V or less is detected at the power source of the rear acceleration sensor (absorber control ECU) for 0.5 seconds.
  • With the engine switch on (IG), a voltage of 4.7 V or more, or 0.3 V or less is detected at the rear acceleration sensor (absorber control ECU) for 1 second.
  • Sensor output value is +/- 0.0639 m/s2 continuously for 300 seconds.

Absorber control ECU

Does not come on

Yes

C1796

(Up&Down)G Sensor FR

With the vehicle stationary on a level surface, an acceleration sensor value that is within -1.96 to 1.96 m/s2 is not received from the acceleration sensor assembly RH for 1 second or more.
  • Acceleration sensor assembly RH
  • Wire harness or connector
  • Absorber control ECU

Test mode

(Test mode)

C1797

(Up&Down)G Sensor FL

With the vehicle stationary on a level surface, an acceleration sensor value that is within -1.96 to 1.96 m/s2 is not received from the acceleration sensor assembly LH for 1 second or more.
  • Acceleration sensor assembly LH
  • Wire harness or connector
  • Absorber control ECU

Test mode

(Test mode)

C1798

(Up&Down)G Sensor Rear

With the vehicle stationary on a level surface, an acceleration sensor value that is within -1.96 to 1.96 m/s2 is not received from the rear acceleration sensor (absorber control ECU) for 1 second or more.

Absorber control ECU

Test mode

(Test mode)
DTC Detection Conditions: C1715
 

Vehicle Condition

Pattern 1

Pattern 2

Pattern 3

Pattern 4

Pattern 5

Diagnosis Condition

Engine switch is on (IG)

â—‹

â—‹

â—‹

â—‹

â—‹

Malfunction Status

Sensor power source voltage is 4.3 V or less

â—‹

-

-

-

-

Sensor power source voltage is 5.5 V or higher

-

â—‹

-

-

-

Output voltage is 0.3 V or less

-

-

â—‹

-

-

Output voltage is 4.7 V or higher

-

-

-

â—‹

-

Sensor output value is +/- 0.0639 m/s2

-

-

-

-

â—‹

Detection Time

0.5 seconds or more

0.5 seconds or more

1 second or more

1 second or more

300 seconds or more

Number of Trips

1 trip

1 trip

1 trip

1 trip

1 trip

HINT:

DTC will be stored when the conditions of any pattern in the table above are met.

DTC Detection Conditions: C1716
 

Vehicle Condition

Pattern 1

Pattern 2

Pattern 3

Pattern 4

Pattern 5

Diagnosis Condition

Engine switch is on (IG)

â—‹

â—‹

â—‹

â—‹

â—‹

Malfunction Status

Sensor power source voltage is 4.3 V or less

â—‹

-

-

-

-

Sensor power source voltage is 5.5 V or higher

-

â—‹

-

-

-

Output voltage is 0.3 V or less

-

-

â—‹

-

-

Output voltage is 4.7 V or higher

-

-

-

â—‹

-

Sensor output value is +/- 0.0639 m/s2

-

-

-

-

â—‹

Detection Time

0.5 seconds or more

0.5 seconds or more

1 second or more

1 second or more

300 seconds or more

Number of Trips

1 trip

1 trip

1 trip

1 trip

1 trip

HINT:

DTC will be stored when the conditions of any pattern in the table above are met.

DTC Detection Conditions: C1717
 

Vehicle Condition

Pattern 1

Pattern 2

Pattern 3

Pattern 4

Pattern 5

Diagnosis Condition

Engine switch is on (IG)

â—‹

â—‹

â—‹

â—‹

â—‹

Malfunction Status

Sensor power source voltage is 4.3 V or less

â—‹

-

-

-

-

Sensor power source voltage is 5.5 V or higher

-

â—‹

-

-

-

Output voltage is 0.3 V or less

-

-

â—‹

-

-

Output voltage is 4.7 V or higher

-

-

-

â—‹

-

Sensor output value is +/- 0.0639 m/s2

-

-

-

-

â—‹

Detection Time

0.5 seconds or more

0.5 seconds or more

1 second or more

1 second or more

300 seconds or more

Number of Trips

1 trip

1 trip

1 trip

1 trip

1 trip

HINT:

DTC will be stored when the conditions of any pattern in the table above are met.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Before performing troubleshooting, inspect the connectors of related circuits.
  • If DTC C1782 (Power Source Voltage Malfunction) is output at the same time, perform troubleshooting for C1782 first.

    Click here

  • Before replacing the absorber control ECU, perform all of the following:
    • Symptom simulation.

      Click here

    • DTC inspection.

      Click here

    • Techstream inspection.

      Click here

      • If no malfunctions are found in other areas, replace the absorber control ECU.
  • After replacing the absorber control ECU with a new one, perform registration of vehicle identification information.

    Click here

PROCEDURE

1.

READ VALUE USING TECHSTREAM ((UP & DOWN) G SENSOR)

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / Air suspension / Data List.

Chassis > Air suspension > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

(Up&Down)G Sensor FR

Front acceleration sensor RH (up and down)

Min.: -1045.29 m/s2

Max.: 1045.26 m/s2

-0.98 to 0.98 m/s2

when stationary

The value changes when the vehicle (front RH) is bounced.

(Up&Down)G Sensor FL

Front acceleration sensor LH (up and down)

Min.: -1045.29 m/s2

Max.: 1045.26 m/s2

-0.98 to 0.98 m/s2

when stationary

The value changes when the vehicle (front LH) is bounced.

(Up&Down)G Sensor Rear

Rear acceleration sensor (up and down)

Min.: -1045.29 m/s2

Max.: 1045.26 m/s2

-0.98 to 0.98 m/s2

when stationary

The value changes when the vehicle (rear) is bounced.
Chassis > Air suspension > Data List

Tester Display

(Up&Down)G Sensor FR

(Up&Down)G Sensor FL

(Up&Down)G Sensor Rear

OK:

The values are as specified in the normal condition column.

Result

Proceed to

OK

A

NG (front RH or front LH)

B

NG (rear)

C
B

GO TO STEP 3

C

REPLACE ABSORBER CONTROL ECU

A

2.

CHECK FOR DTCS

(a) Clear the DTCs.

Click here

Chassis > Air suspension > Clear DTCs

(b) Turn the engine switch off.

(c) Check for DTCs.

Click here

Chassis > Air suspension > Trouble Codes

Result

Proceed to

DTCs are output (front RH or front LH)

A

DTCs are output (rear)

B

DTCs are not output

C
B

REPLACE ABSORBER CONTROL ECU

C

USE SIMULATION METHOD TO CHECK

A

3.

INSPECT ACCELERATION SENSOR ASSEMBLY

(a) Turn the engine switch off.

(b) Remove the acceleration sensor assembly RH or acceleration sensor assembly LH.

Click here

(c) Inspect the acceleration sensor assembly RH or acceleration sensor assembly LH.

Click here

Result

Proceed to

OK

A

NG (Acceleration sensor assembly RH malfunction)

B

NG (Acceleration sensor assembly LH malfunction)

C
B

REPLACE ACCELERATION SENSOR ASSEMBLY RH

C

REPLACE ACCELERATION SENSOR ASSEMBLY LH

A

4.

CHECK HARNESS AND CONNECTOR (ACCELERATION SENSOR ASSEMBLY - ABSORBER CONTROL ECU)

(a) Check the acceleration sensor assembly RH harness and connector (when DTC C1715 is output).

(1) Disconnect the K59 absorber control ECU connector.

(2) Disconnect the K61 acceleration sensor assembly RH connector.

(3) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

K61-1 (SGFR) - K59-23 (SGS1)

Always

Below 1 Ω

K61-2 (SGG) - K59-22 (SGG1)

Always

Below 1 Ω

K61-3 (SGB) - K59-14 (SGB1)

Always

Below 1 Ω

K61-1 (SGFR) or K59-23 (SGS1) - Body ground

Always

10 kΩ or higher

K61-2 (SGG) or K59-22 (SGG1) - Body ground

Always

10 kΩ or higher

K61-3 (SGB) or K59-14 (SGB1) - Body ground

Always

10 kΩ or higher

(b) Check the acceleration sensor assembly LH harness and connector (when DTC C1716 is output).

(1) Disconnect the K59 absorber control ECU connector.

(2) Disconnect the A46 acceleration sensor assembly LH connector.

(3) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

A46-1 (SGFL) - K59-25 (SGS2)

Always

Below 1 Ω

A46-2 (SGG) - K59-24 (SGG2)

Always

Below 1 Ω

A46-3 (SGB) - K59-15 (SGB2)

Always

Below 1 Ω

A46-1 (SGFL) or K59-25 (SGS2) - Body ground

Always

10 kΩ or higher

A46-2 (SGG) or K59-24 (SGG2) - Body ground

Always

10 kΩ or higher

A46-3 (SGB) or K59-15 (SGB2) - Body ground

Always

10 kΩ or higher
OK

REPLACE ABSORBER CONTROL ECU

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

FR Damping Force Control Actuator Circuit (C1731-C1734)

DESCRIPTION

The absorber control actuator changes the damping force depending on absorber control ECU signals.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

C1731

FR Damping Force Control Actuator Circuit

Either condition is met:

  • An open circuit is detected between the front absorber control actuator RH (front shock absorber assembly RH) and absorber control ECU.
  • A short circuit is detected between the front absorber control actuator RH (front shock absorber assembly RH) and absorber control ECU.
  • Front absorber control actuator RH (front shock absorber assembly RH)
  • Front skid control sensor wire RH
  • Wire harness or connector
  • Absorber control ECU

Does not come on

Yes

C1732

FL Damping Force Control Actuator Circuit

Either condition is met:

  • An open circuit is detected between the front absorber control actuator LH (front shock absorber assembly LH) and absorber control ECU.
  • A short circuit is detected between the front absorber control actuator LH (front shock absorber assembly LH) and absorber control ECU.
  • Front absorber control actuator LH (front shock absorber assembly LH)
  • Front skid control sensor wire LH
  • Wire harness or connector
  • Absorber control ECU

Does not come on

Yes

C1733

RR Damping Force Control Actuator Circuit

Either condition is met:

  • An open circuit is detected between the rear absorber control actuator RH (rear shock absorber assembly RH) and absorber control ECU.
  • A short circuit is detected between the rear absorber control actuator RH (rear shock absorber assembly RH) and absorber control ECU.
  • Rear absorber control actuator RH (rear shock absorber assembly RH)
  • Skid control sensor wire RH (No. 1 parking brake wire assembly)
  • Wire harness or connector
  • Absorber control ECU

Does not come on

Yes

C1734

RL Damping Force Control Actuator Circuit

Either condition is met:

  • An open circuit is detected between the rear absorber control actuator LH (rear shock absorber assembly LH) and absorber control ECU.
  • A short circuit is detected between the rear absorber control actuator LH (rear shock absorber assembly LH) and absorber control ECU.
  • Rear absorber control actuator LH (rear shock absorber assembly LH)
  • Skid control sensor wire LH (No. 2 parking brake wire assembly)
  • Wire harness or connector
  • Absorber control ECU

Does not come on

Yes

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Before performing troubleshooting, inspect the connectors of related circuits.
  • If DTC C1782 (Power Source Voltage Malfunction) is output at the same time, perform troubleshooting for C1782 first.

    Click here

  • Before replacing the absorber control ECU, perform all of the following:
    • Symptom simulation.

      Click here

    • DTC inspection.

      Click here

    • Techstream inspection.

      Click here

      • If no malfunctions are found in other areas, replace the absorber control ECU.
  • After replacing the absorber control ECU with a new one, perform registration of vehicle identification information.

    Click here

PROCEDURE

1.

CLEAR DTCS

(a) Clear the DTCs.

Click here

Chassis > Air suspension > Clear DTCs
NEXT

2.

PERFORM ACTIVE TEST USING TECHSTREAM (FOUR-WHEEL DAMPING FORCE FULL HARD/SOFT)

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Start the engine.

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / Air suspension /Active Test.

Chassis > Air suspension > Active Test

Tester Display

Measurement Item

Restrict Condition

Four-Wheel Damping Force Full Hard

Four-wheel damper step fixed at full hard
  • Vehicle stopped
  • Engine idling
  • When the absorber control actuator is normal
  • When the power source voltage is normal

Four-Wheel Damping Force Full Soft

Four-wheel damper step fixed at full soft
  • Vehicle stopped
  • Engine idling
  • When the absorber control actuator is normal
  • When the power source voltage is normal
Chassis > Air suspension > Active Test

Tester Display

Four-Wheel Damping Force Full Hard
Chassis > Air suspension > Active Test

Tester Display

Four-Wheel Damping Force Full Soft

(f) When performing the Active Test, read each Tester Display item for the applicable wheel on the Data List and check the operation status of the absorber control actuator for the applicable wheel.

Chassis > Air suspension > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

FR Solenoid Aim Electric Current Level for Control

Target solenoid current value (front wheel RH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

FL Solenoid Aim Electric Current Level for Control

Target solenoid current value (front wheel LH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

RR Solenoid Aim Electric Current Level for Control

Target solenoid current value (rear wheel RH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

RL Solenoid Aim Electric Current Level for Control

Target solenoid current value (rear wheel LH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

FR Solenoid Drive Duty

Solenoid drive duty value (front wheel RH)

Min.: 0%

Max.: 100%

Changes depending on target damping force

-

FL Solenoid Drive Duty

Solenoid drive duty value (front wheel LH)

Min.: 0%

Max.: 100%

Changes depending on target damping force

-

RR Solenoid Drive Duty

Solenoid drive duty value (rear wheel RH)

Min.: 0%

Max.: 100%

Changes depending on target damping force

-

RL Solenoid Drive Duty

Solenoid drive duty value (rear wheel LH)

Min.: 0%

Max.: 100%

Changes depending on target damping force

-

FR Solenoid Electric Current

Solenoid current value (front wheel RH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

FL Solenoid Electric Current

Solenoid current value (front wheel LH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

RR Solenoid Electric Current

Solenoid current value (rear wheel RH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

RL Solenoid Electric Current

Solenoid current value (rear wheel LH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-
Chassis > Air suspension > Data List

Tester Display

FR Solenoid Aim Electric Current Level for Control

FL Solenoid Aim Electric Current Level for Control

RR Solenoid Aim Electric Current Level for Control

RL Solenoid Aim Electric Current Level for Control

FR Solenoid Drive Duty

FL Solenoid Drive Duty

RR Solenoid Drive Duty

RL Solenoid Drive Duty

FR Solenoid Electric Current

FL Solenoid Electric Current

RR Solenoid Electric Current

RL Solenoid Electric Current

OK:

The Data List step numbers, drive duty values and current values change according to the operation of the Active Test.

NG

GO TO STEP 4

OK

3.

RECONFIRM DTC

(a) Check that the same DTC is output.

Click here

Chassis > Air suspension > Trouble Codes

Result

Proceed to

DTC is output

A

DTC is not output

B
B

USE SIMULATION METHOD TO CHECK

A

4.

INSPECT ABSORBER CONTROL ACTUATOR (SHOCK ABSORBER ASSEMBLY)

(a) Turn the engine switch off.

(b) Inspect the absorber control actuator (shock absorber assembly).

for Front Side: Click here

for Rear Side: Click here

Result

Proceed to

OK (for Front Side)

A

OK (for Rear Side)

B

NG (Front absorber control actuator RH (front shock absorber assembly RH) malfunction)

C

NG (Front absorber control actuator LH (front shock absorber assembly LH) malfunction)

D

NG (Rear absorber control actuator RH (rear shock absorber assembly RH) malfunction)

E

NG (Rear absorber control actuator LH (rear shock absorber assembly LH) malfunction)

F
B

GO TO STEP 7

C

REPLACE FRONT ABSORBER CONTROL ACTUATOR RH (FRONT SHOCK ABSORBER ASSEMBLY RH)

D

REPLACE FRONT ABSORBER CONTROL ACTUATOR LH (FRONT SHOCK ABSORBER ASSEMBLY LH)

E

REPLACE REAR ABSORBER CONTROL ACTUATOR RH (REAR SHOCK ABSORBER ASSEMBLY RH)

F

REPLACE REAR ABSORBER CONTROL ACTUATOR LH (REAR SHOCK ABSORBER ASSEMBLY LH)

A

5.

INSPECT FRONT SKID CONTROL SENSOR WIRE

(a) Disconnect the z14 or z13 front skid control sensor wire connector.

(b) Disconnect the A58 or A60 front skid control sensor wire connector.

(c) Measure the resistance according to the value(s) in the table below.

*A

for RH

*B

for LH

*a

Component without harness connected (Front Skid Control Sensor Wire)

-

-

Standard Resistance:

for RH

Tester Connection

Condition

Specified Condition

z14-2 - A58-2 (FAR+)

Always

Below 1 Ω

z14-1 - A58-1 (FAR-)

z14-2 or A58-2 (FAR+) - Body ground and other terminals

Always

10 kΩ or higher

z14-1 or A58-1 (FAR-) - Body ground and other terminals
for LH

Tester Connection

Condition

Specified Condition

z13-2 - A60-2 (FAL+)

Always

Below 1 Ω

z13-1 - A60-1 (FAL-)

z13-2 or A60-2 (FAL+) - Body ground and other terminals

Always

10 kΩ or higher

z13-1 or A60-1 (FAL-) - Body ground and other terminals

Result

Proceed to

OK

A

NG (for RH)

B

NG (for LH)

C
B

REPLACE FRONT SKID CONTROL SENSOR WIRE RH

C

REPLACE FRONT SKID CONTROL SENSOR WIRE LH

A

6.

CHECK HARNESS AND CONNECTOR (FRONT SKID CONTROL SENSOR WIRE - ABSORBER CONTROL ECU)

(a) Disconnect the K59 absorber control ECU connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

for RH

Tester Connection

Condition

Specified Condition

A58-2 (FAR+) - K59-5 (FAR+)

Always

Below 1 Ω

A58-1 (FAR-) - K59-6 (FAR-)

A58-2 (FAR+) or K59-5 (FAR+) - Body ground and other terminals

Always

10 kΩ or higher

A58-1 (FAR-) or K59-6 (FAR-) - Body ground and other terminals
for LH

Tester Connection

Condition

Specified Condition

A60-2 (FAL+) - K59-2 (FAL+)

Always

Below 1 Ω

A60-1 (FAL-) - K59-3 (FAL-)

A60-2 (FAL+) or K59-2 (FAL+) - Body ground and other terminals

Always

10 kΩ or higher

A60-1 (FAL-) or K59-3 (FAL-) - Body ground and other terminals
OK

REPLACE ABSORBER CONTROL ECU

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

7.

INSPECT SKID CONTROL SENSOR WIRE (PARKING BRAKE WIRE ASSEMBLY)

(a) Disconnect the Y6 or Y3 skid control sensor wire (parking brake wire assembly) connector.

(b) Disconnect the YK3 or YK4 skid control sensor wire (parking brake wire assembly) connector.

(c) Measure the resistance according to the value(s) in the table below.

*A

for RH

*B

for LH

*a

Component without harness connected (Skid Control Sensor Wire (Parking Brake Wire Assembly))

-

-

Standard Resistance:

for RH

Tester Connection

Condition

Specified Condition

Y6-1 - YK3-3

Always

Below 1 Ω

Y6-3 - YK3-4

Y6-1 or YK3-3 - Body ground and other terminals

Always

10 kΩ or higher

Y6-3 or YK3-4 - Body ground and other terminals
for LH

Tester Connection

Condition

Specified Condition

Y3-1 - YK4-3

Always

Below 1 Ω

Y3-3 - YK4-4

Y3-1 or YK4-3 - Body ground and other terminals

Always

10 kΩ or higher

Y3-3 or YK4-4 - Body ground and other terminals

Result

Proceed to

OK

A

NG (for RH)

B

NG (for LH)

C
B

REPLACE SKID CONTROL SENSOR WIRE RH (NO. 1 PARKING BRAKE WIRE ASSEMBLY)

C

REPLACE SKID CONTROL SENSOR WIRE LH (NO. 2 PARKING BRAKE WIRE ASSEMBLY)

A

8.

CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE (PARKING BRAKE WIRE ASSEMBLY) - ABSORBER CONTROL ECU)

(a) Disconnect the K60 absorber control ECU connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

for RH

Tester Connection

Condition

Specified Condition

YK3-3 - K60-6 (RAR+)

Always

Below 1 Ω

YK3-4 - K60-5 (RAR-)

YK3-3 or K60-6 (RAR+) - Body ground and other terminals

Always

10 kΩ or higher

YK3-4 or K60-5 (RAR-) - Body ground and other terminals
for LH

Tester Connection

Condition

Specified Condition

YK4-3 - K60-2 (RAL+)

Always

Below 1 Ω

YK4-4 - K60-1 (RAL-)

YK4-3 or K60-2 (RAL+) - Body ground and other terminals

Always

10 kΩ or higher

YK4-4 or K60-1 (RAL-) - Body ground and other terminals
OK

REPLACE ABSORBER CONTROL ECU

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

Suspension Control ECU Malfunction (C1781)

DESCRIPTION

If a malfunction in the absorber control ECU is detected, DTC C1781 is stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

C1781

Suspension Control ECU Malfunction

One of the following conditions is met:

  • A nonvolatile memory write or read error occurs.
  • A CAN communication register is stuck.
  • An overheat protection function malfunction occurs.
  • Absorber control ECU
  • CAN communication system

Does not come on

Yes

CAUTION / NOTICE / HINT

NOTICE:

  • Before performing troubleshooting, inspect the connectors of related circuits.
  • If DTC C1782 (Power Source Voltage Malfunction) is output at the same time, perform troubleshooting for C1782 first.

    Click here

  • Before replacing the absorber control ECU, perform all of the following:
    • Symptom simulation.

      Click here

    • DTC inspection.

      Click here

    • Techstream inspection.

      Click here

      • If no malfunctions are found in other areas, replace the absorber control ECU.
  • After replacing the absorber control ECU with a new one, perform registration of vehicle identification information.

    Click here

PROCEDURE

1.

CHECK FOR DTCS (CAN COMMUNICATION SYSTEM)

(a) Check for DTCs.

Click here

Chassis > Air suspension > Trouble Codes

Result

Proceed to

CAN DTCs are not output

A

CAN DTCs are output

B
A

REPLACE ABSORBER CONTROL ECU

B

GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING)

Low Battery Positive Voltage (C1782)

DESCRIPTION

This DTC (C1782) is output if voltage matching the DTC detection condition continues to be supplied to the IGB terminal of the absorber control ECU due to malfunctions in the power source or charging circuits, such as the battery or generator assembly circuits.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

C1782

Low Battery Positive Voltage

While the engine switch is on (IG), the voltage at terminal IGB is 10 V or less, or 16 V or more for 0.5 seconds.
  • AVS fuse
  • IG1 NO. 3 relay
  • Battery
  • Charging system
  • Wire harness or connector
  • Absorber control ECU

Does not come on

No

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Before performing troubleshooting, inspect the connectors of related circuits.
  • Before replacing the absorber control ECU, perform all of the following:
    • Symptom simulation.

      Click here

    • DTC inspection.

      Click here

    • Techstream inspection.

      Click here

      • If no malfunctions are found in other areas, replace the absorber control ECU.
  • After replacing the absorber control ECU with a new one, perform registration of vehicle identification information.

    Click here

  • Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.

READ VALUE USING TECHSTREAM (IG POWER SOURCE VOLTAGE)

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / Air suspension / Data List.

Chassis > Air suspension > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

IG Power Source Voltage

ECU power supply voltage

Min.: 0.0 V

Max.: 25.5 V

11 to 14 V (Actual ECU power supply voltage): Engine switch on (IG)

-
Chassis > Air suspension > Data List

Tester Display

IG Power Source Voltage

OK:

The value is as specified in the normal condition column.

NG

GO TO STEP 3

OK

2.

CHECK FOR DTCS

(a) Clear the DTCs.

Click here

Chassis > Air suspension > Clear DTCs

(b) Turn the engine switch off.

(c) Check for DTCs.

Click here

Chassis > Air suspension > Trouble Codes

Result

Proceed to

DTC is not output

A

DTC is output

B
A

USE SIMULATION METHOD TO CHECK

B

REPLACE ABSORBER CONTROL ECU

3.

INSPECT BATTERY

(a) Check the battery voltage.

Standard Voltage:

11 to 14 V

NG

CHECK OR REPLACE CHARGING SYSTEM OR BATTERY

OK

4.

INSPECT IG1 NO. 3 RELAY

(a) Turn the engine switch off.

(b) Inspect the IG1 NO. 3 relay.

Click here

NG

REPLACE IG1 NO. 3 RELAY
OK

5.

CHECK HARNESS AND CONNECTOR (POWER SOURCE - IG1 NO. 3 RELAY)

(a) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

1 (IG1 NO. 3 relay) - Body ground

Engine switch on (IG)

11 to 14 V

5 (IG1 NO. 3 relay) - Body ground

Always

11 to 14 V
NG

CHECK OR REPLACE CHARGING SYSTEM OR BATTERY

OK

6.

CHECK HARNESS AND CONNECTOR (IG1 NO. 3 RELAY - ABSORBER CONTROL ECU AND BODY GROUND)

(a) Disconnect the K59 absorber control ECU connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

3 (IG1 NO. 3 relay) - K59-1 (IGB)

Always

Below 1 Ω

3 (IG1 NO. 3 relay) or K59-1 (IGB) - Body ground

Always

10 kΩ or higher

2 (IG1 NO. 3 relay) - Body ground

Always

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

7.

CHECK HARNESS AND CONNECTOR (ABSORBER CONTROL ECU - BODY GROUND)

(a) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

K59-4 (GND) - Body ground

Always

Below 1 Ω
OK

REPLACE ABSORBER CONTROL ECU

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

Front Wheels Speed Sensor Signal Malfunction (C1783)

DESCRIPTION

The speed sensors monitor the speed of the wheels and send an appropriate speed signal to the absorber control ECU through the skid control ECU (brake actuator assembly).

If a malfunction occurs in either a front speed sensor or rear speed sensor, DTC C1783 is stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

C1783

Front Wheels Speed Sensor Signal Malfunction

A speed sensor malfunction signal from the skid control ECU (brake actuator assembly) is detected for 1 second or more.

Electronically controlled brake system

Does not come on

Yes

PROCEDURE

1.

GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM

(a) Go to electronically controlled brake system.

Click here

NEXT

END

Steering Sensor Signal Malfunction (C1784)

DESCRIPTION

Steering sensor signals are sent to the absorber control ECU via CAN communication.

If a communication error is detected, DTC C1784 is stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

C1784

Steering Sensor Signal Malfunction

A steering sensor communication error is detected, or a steering sensor power malfunction is detected for 5 seconds or more.

Electronically controlled brake system

Does not come on

Yes

(Under some of the detection conditions (sensor power +B open malfunction is detected), DTC is not stored.)

PROCEDURE

1.

GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM

(a) Go to electronically controlled brake system.

Click here

NEXT

END

Master Cylinder Pressure Circuit (C1786)

DESCRIPTION

The absorber control ECU stores this DTC when a malfunction signal from the master cylinder pressure sensor built into the brake actuator assembly is received via CAN communication.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

C1786

Master Cylinder Pressure Circuit

A master cylinder pressure sensor malfunction signal is continuously received from the skid control ECU (brake actuator assembly) for 3 seconds or more.

Electronically controlled brake system

Does not come on

Yes

PROCEDURE

1.

GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM

(a) Go to electronically controlled brake system.

Click here

NEXT

END

(Horizontality) G Sensor Malfunction (C1787)

DESCRIPTION

The absorber control ECU receives a signal from the yaw rate and acceleration sensor (airbag ECU assembly) via CAN communication.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

C1787

(Horizontality) G Sensor Malfunction

While the engine switch is on (IG), yaw rate and acceleration sensor (airbag ECU assembly) malfunction signal is detected for 1 second or more.

Electronically controlled brake system

Does not come on

Yes

PROCEDURE

1.

GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM

(a) Go to electronically controlled brake system.

Click here

NEXT

END

Vehicle Identification Malfunction (C1789)

DESCRIPTION

When the absorber control ECU has not acquired the vehicle identification information, DTC C1789 is stored. When the vehicle identification information is correctly acquired, this DTC is cleared. Vehicle identification information is automatically acquired when the system enters test mode.

If an incorrect ECM is installed, the vehicle information will not match and DTC C1789 will be stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

C1789

Vehicle Identification Malfunction

One of the following conditions is met:

  • The vehicle identification information is not stored.
  • Vehicle identification information that is different from the stored information is received 3 times.
  • Vehicle identification information
  • ECM
  • CAN communication system
  • Absorber control ECU

Does not come on

Yes

(Under some of the detection conditions (control map non-retrieval is not stored), DTC is not stored.)

CAUTION / NOTICE / HINT

NOTICE:

  • Before performing troubleshooting, inspect the connectors of related circuits.
  • If DTC C1782 (Power Source Voltage Malfunction) is output at the same time, perform troubleshooting for C1782 first.

    Click here

  • Before replacing the absorber control ECU, perform all of the following:
    • Symptom simulation.

      Click here

    • DTC inspection.

      Click here

    • Techstream inspection.

      Click here

      • If no malfunctions are found in other areas, replace the absorber control ECU.
  • After replacing the absorber control ECU with a new one, perform registration of vehicle identification information.

    Click here

PROCEDURE

1.

CHECK FOR DTCS

(a) Check for DTCs.

Click here

Chassis > Air suspension > Trouble Codes

HINT:

If DTC C1781 (Suspension Control ECU Malfunction) is output at the same time, perform troubleshooting for C1781 first.

Result

Proceed to

C1781 and CAN communication malfunction DTC are not output

A

C1781 is output

B

CAN communication DTC is output

C
B

GO TO C1781

C

GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING)

A

2.

CHECK VEHICLE IDENTIFICATION INFORMATION STATUS

(a) Check that vehicle identification information has been stored.

Click here

Result

Proceed to

Information stored

A

Information not stored

B
B

PERFORM VEHICLE IDENTIFICATION INFORMATION REGISTRATION

A

3.

CHECK RELATED PART

(a) If the DTC was output as a result of the replacement of a related part, replace the part with one that has a correct part number.

Related Part

ECM

NOTICE:

When removing a related part to check it, be sure to follow the appropriate procedures and precautions.

Refer to the following procedures to remove the ECM.

Click here

HINT:

If parts have not been replaced and DTC C1789 is output, there may be an internal malfunction in the absorber control ECU. Therefore, replace the absorber control ECU.

Result

Proceed to

The related part has an incorrect part number

A

The related part has the correct part number, or a related part and absorber control ECU have not been replaced

B
A

REPLACE RELATED PART WITH PART THAT HAS CORRECT PART NUMBER

B

REPLACE ABSORBER CONTROL ECU

Customize Parameters

CUSTOMIZE PARAMETERS

CUSTOMIZE ADAPTIVE VARIABLE SUSPENSION SYSTEM

HINT:

"Custom" mode can be selected by using the drive mode select switch (electric parking brake switch assembly).

(a) Customizing with the multi-display

(1) Turn the engine switch on (IG).

(2) Enter the following menus: MENU / Setup / Vehicle / Vehicle Customization / Drive Mode Customization.

(3) Select the setting by referring to the table below.

Display

Content

Default

Setting

Powertrain

Acceleration response, etc.

Normal

Power / Normal / Eco

Chassis

Damping force of suspension, steering assist force, etc.

Normal

Sport / Normal

Climate

Effectiveness of air conditioning system, etc.

Normal

Normal / Eco

Data List / Active Test

DATA LIST / ACTIVE TEST

READ DATA LIST

NOTICE:

In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not.

HINT:

Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time.

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / Air suspension / Data List.

(f) Read the Data List according to the display on the Techstream.

Chassis > Air suspension > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

(Up&Down)G Sensor FR

Front acceleration sensor RH (up and down)

Min.: -1045.29 m/s2

Max.: 1045.26 m/s2

-0.98 to 0.98 m/s2 when stationary

The value changes when the vehicle (front RH) is bounced.

(Up&Down)G Sensor FL

Front acceleration sensor LH (up and down)

Min.: -1045.29 m/s2

Max.: 1045.26 m/s2

-0.98 to 0.98 m/s2 when stationary

The value changes when the vehicle (front LH) is bounced.

(Up&Down)G Sensor Rear

Rear acceleration sensor (up and down)

Min.: -1045.29 m/s2

Max.: 1045.26 m/s2

-0.98 to 0.98 m/s2 when stationary

The value changes when the vehicle (rear) is bounced.

Gravity Sensor(Side to Side)

Lateral acceleration sensor (side to side)

Min.: -1176.37 m/s2

Max.: 1176.33 m/s2

Changes depending on acceleration generated when turning

-

Stop Light Switch

Stop light switch

OFF or ON

OFF: Brake pedal released

ON: Brake pedal depressed

-

SPORT Switch

Drive mode select switch

OFF or ON

OFF: Not in Sport S+ mode or Custom mode (when the Chassis item is set to SPORT)

ON: During Sport S+ mode or Custom mode (when the Chassis item is set to SPORT)

-

HV Ready

HV ready status

OFF or ON

OFF: Always

This item is displayed on the Techstream but is not required for diagnosis or repair.

TC Terminal

TC terminal status

OFF or ON

OFF: DTC not output

ON: DTC output

-

TS Terminal

TS terminal status

OFF or ON

OFF: During normal mode

ON: During test mode

-

IG Power Source Voltage

ECU power supply voltage

Min.: 0.0 V

Max.: 25.5 V

11 to 14 V (Actual ECU power supply voltage): Engine switch on (IG)

-

Steering Angle

Steering angle sensor reading

Min.: -49152.0 deg

Max.: 49150.5 deg

Actual steering angle

Steering wheel turned left: Reading increases

Steering wheel turned right: Reading decreases

-

Engine Speed

Engine speed

Min.: 0 rpm

Max.: 25500 rpm

Actual engine speed

-

FR Wheel Speed

Front speed sensor RH reading

Min.: 0 km/h (0 mph)

Max.: 255 km/h (159 mph)

Actual vehicle speed

No large fluctuations when driving at a constant speed.

FL Wheel Speed

Front speed sensor LH reading

Min.: 0 km/h (0 mph)

Max.: 255 km/h (159 mph)

Actual vehicle speed

No large fluctuations when driving at a constant speed.

RR Wheel Speed

Rear speed sensor RH reading

Min.: 0 km/h (0 mph)

Max.: 255 km/h (159 mph)

Actual vehicle speed

No large fluctuations when driving at a constant speed.

RL Wheel Speed

Rear speed sensor LH reading

Min.: 0 km/h (0 mph)

Max.: 255 km/h (159 mph)

Actual vehicle speed

No large fluctuations when driving at a constant speed.

Driving Torque

Driving torque

Min.: -1024 Nm

Max.: 1023 Nm

Changes in accordance with accelerator pedal position

-

Adaptive Variable Suspension(AVS) Mode

Adaptive variable suspension system (AVS) mode

NORMAL, COMFORT, SEMI CO, SEMI SP or SPORTS

NORMAL: Not in Sport S+ mode or Custom mode (when the Chassis item is set to SPORT)

SPORTS: During Sport S+ mode or Custom mode (when the Chassis item is set to SPORT)

-

Compatible Constant Information

Information used to change the compatible constant

Min.: 0

Max.: 255

-

-

Identical Constant Information

Information used to change the identical constant

Min.: 0

Max.: 255

-

-

Design Constant Information

Information used to change the design constant

Min.: 0

Max.: 255

-

-

AVS Control Information FR

AVS control information (front wheel RH)

Min.: 0

Max.: 255

-

-

AVS Control Information FL

AVS control information (front wheel LH)

Min.: 0

Max.: 255

-

-

AVS Control Information RR

AVS control information (rear wheel RH)

Min.: 0

Max.: 255

-

-

AVS Control Information RL

AVS control information (rear wheel LH)

Min.: 0

Max.: 255

-

-

Vehicle Information (Conv/HV)

Vehicle identification information (hybrid vehicle or except hybrid vehicle)

Unknown, Conv or HV

Conv: When vehicle identification normal

-

Stop and Start Learning Status

Learning status of stop and start setting availability after vehicle identification information registration is performed

Unset, OFF or ON

OFF

-

Overheat Protection Control Count

Number of times overheat protection was performed in past

Min.: 0

Max.: 255

Displays number of times overheat protection was performed in past

-

ECU Substrate Maximum Temperature

Stored ECU substrate maximum temperature

Min.: 40°C

Max.: 120°C

Displays maximum temperature of ECU substrate in past

-

Status of Overheat Protection Control

Current overheat protection status

OFF or ON

OFF: No overheat protection

ON: When overheat protection is on, damping force control stops until the temperature drops below a certain value.

G Sensor Voltage

G sensor power supply voltage

Min.: 0.0 V

Max.: 25.5 V

4.8 to 5.2 V

-

ECU Substrate Temperature

Current ECU substrate temperature

Min.: 40°C

Max.: 120°C

Displays current ECU substrate temperature

-

FR Solenoid Aim Electric Current Level for Control

Target solenoid current value (front wheel RH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

FL Solenoid Aim Electric Current Level for Control

Target solenoid current value (front wheel LH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

RR Solenoid Aim Electric Current Level for Control

Target solenoid current value (rear wheel RH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

RL Solenoid Aim Electric Current Level for Control

Target solenoid current value (rear wheel LH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

FR Solenoid Drive Duty

Solenoid drive duty value (front wheel RH)

Min.: 0%

Max.: 100%

Changes depending on target damping force

-

FL Solenoid Drive Duty

Solenoid drive duty value (front wheel LH)

Min.: 0%

Max.: 100%

Changes depending on target damping force

-

RR Solenoid Drive Duty

Solenoid drive duty value (rear wheel RH)

Min.: 0%

Max.: 100%

Changes depending on target damping force

-

RL Solenoid Drive Duty

Solenoid drive duty value (rear wheel LH)

Min.: 0%

Max.: 100%

Changes depending on target damping force

-

FR Solenoid Electric Current

Solenoid current value (front wheel RH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

FL Solenoid Electric Current

Solenoid current value (front wheel LH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

RR Solenoid Electric Current

Solenoid current value (rear wheel RH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

RL Solenoid Electric Current

Solenoid current value (rear wheel LH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

Air suspension Learning Status

Learning status of air suspension system setting availability after vehicle identification information registration is performed

Unset, OFF or ON

OFF

-

Number of Trouble Codes

Number of DTCs stored

Min.: 0

Max.: 255

0

-

PERFORM ACTIVE TEST

HINT:

Using the Techstream to perform Active Tests allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Tests early in troubleshooting is one way to save diagnosis time. Data List information can be displayed while performing Active Tests.

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Start the engine.

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / Air suspension / Active Test.

(f) Perform the Active Test according to the display on the Techstream.

Chassis > Air suspension > Active Test

Tester Display

Measurement Item

Restrict Condition

Four-Wheel Damping Force Full Hard

Four-wheel damping force fixed at full hard
  • Vehicle stopped
  • Engine idling
  • When the absorber control actuator is normal
  • When the power source voltage is normal

Four-Wheel Damping Force Full Soft

Four-wheel damper step fixed at full soft
  • Vehicle stopped
  • Engine idling
  • When the absorber control actuator is normal
  • When the power source voltage is normal

Damper Step FR (Electric Current)

Changes damping force (front RH)
  • Vehicle stopped
  • Engine idling
  • When the absorber control actuator is normal
  • When the power source voltage is normal

Damper Step FL (Electric Current)

Changes damping force (front LH)
  • Vehicle stopped
  • Engine idling
  • When the absorber control actuator is normal
  • When the power source voltage is normal

Damper Step RR (Electric Current)

Changes damping force (rear RH)
  • Vehicle stopped
  • Engine idling
  • When the absorber control actuator is normal
  • When the power source voltage is normal

Damper Step RL (Electric Current)

Changes damping force (rear LH)
  • Vehicle stopped
  • Engine idling
  • When the absorber control actuator is normal
  • When the power source voltage is normal

Diagnosis System

DIAGNOSIS SYSTEM

DIAGNOSIS SYSTEM

(a) DTCs (normal mode)

(1) DTCs are stored in the absorber control ECU and output by using the Techstream. Refer to the DTC check procedure.

Click here

(b) Test mode

(1) By switching from normal mode to test mode, it is possible to inspect the front acceleration sensor and rear acceleration sensor.

Click here

Diagnostic Trouble Code Chart

DIAGNOSTIC TROUBLE CODE CHART

Adaptive Variable Suspension System

DTC No.

Detection Item

Warning Indicate

Memory

Link

C1715

Front Acceleration Sensor RH Malfunction

Does not come on

Yes

C1716

Front Acceleration Sensor LH Malfunction

Does not come on

Yes

C1717

Rear Acceleration Sensor Malfunction

Does not come on

Yes

C1731

FR Damping Force Control Actuator Circuit

Does not come on

Yes

C1732

FL Damping Force Control Actuator Circuit

Does not come on

Yes

C1733

RR Damping Force Control Actuator Circuit

Does not come on

Yes

C1734

RL Damping Force Control Actuator Circuit

Does not come on

Yes

C1781

Suspension Control ECU Malfunction

Does not come on

Yes

C1782

Low Battery Positive Voltage

Does not come on

No

C1783

Front Wheels Speed Sensor Signal Malfunction

Does not come on

Yes

C1784

Steering Sensor Signal Malfunction

Does not come on

Yes

(Under some of the detection conditions (sensor power +B open malfunction is detected), DTC is not stored.)

C1786

Master Cylinder Pressure Circuit

Does not come on

Yes

C1787

(Horizontality) G Sensor Malfunction

Does not come on

Yes

C1789

Vehicle Identification Malfunction

Does not come on

Yes

(Under some of the detection conditions (control map non-retrieval is not stored), DTC is not stored.)

C1796

(Up&Down)G Sensor FR

Test mode

(Test mode)

C1797

(Up&Down)G Sensor FL

Test mode

(Test mode)

C1798

(Up&Down)G Sensor Rear

Test mode

(Test mode)

U0100

Lost Communication With ECM/PCM "A"

Does not come on

Yes

U0101

Lost Communication with TCM

Does not come on

Yes

U0122

Lost Communication With Vehicle Dynamics Control Module

Does not come on

Yes

U0124

Lost Communication with Lateral Acceleration Sensor Module

Does not come on

Yes

U0126

Lost Communication with Steering Angle Sensor Module

Does not come on

Yes

Dtc Check / Clear

DTC CHECK / CLEAR

CHECK FOR DTC

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / Air suspension / Trouble Codes.

Chassis > Air suspension > Trouble Codes

HINT:

When freeze frame data is stored, check the freeze frame data.

Click here

(f) Read the DTCs by following the prompts on the Techstream screen.

HINT:

Refer to the Techstream operator's manual for further details.

(g) Refer to Diagnostic Trouble Code Chart for DTC information.

Click here

CLEAR DTC

HINT:

After repairing the malfunctions, clear the DTCs.

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / Air suspension / Trouble Codes.

Chassis > Air suspension > Clear DTCs

NOTICE:

DTCs and freeze frame data are cleared at the same time.

(f) Clear the DTCs by following the prompts on the Techstream screen.

HINT:

Refer to the Techstream operator's manual for further details.

Fail-safe Chart

FAIL-SAFE CHART

FAIL-SAFE CHART

Adaptive Variable Suspension System

DTC Chart

Malfunction Item

Fail-safe Operation

C1715

C1716

C1717

Acceleration sensor circuit

Partial control continues.

C1731

C1732

C1733

C1734

Absorber control actuator circuit

Control stops.

C1781

Absorber control ECU

Control stops.

C1782

Power source voltage

Control stops.

C1783

Vehicle speed sensor circuit

Control stops.

C1784

Steering angle sensor

Partial control continues.

C1786

Master cylinder pressure circuit

Partial control continues.

C1787

G sensor (Yaw rate sensor)

Partial control continues.

C1789

Vehicle identification malfunction

Control stops.

U0100

CAN communication system

Partial control continues.

U0101

CAN communication system

Partial control continues.

U0122

CAN communication system

Partial control continues.

U0124

CAN communication system

Partial control continues.

U0126

CAN communication system

Partial control continues.

Freeze Frame Data

FREEZE FRAME DATA

FREEZE FRAME DATA

(a) The absorber control ECU stores system condition information as freeze frame data the moment a DTC is stored. The Freeze Frame Data can be displayed using the Techstream.

(b) Freeze frame data when a DTC is stored.

(1) Freeze frame data is stored the moment a DTC is stored.

(2) When freeze frame data is stored when a DTC is stored, the data is not updated or deleted until DTCs are cleared.

CHECK FREEZE FRAME DATA

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / Air suspension / Trouble Codes.

Chassis > Air suspension > Trouble Codes

(f) Select a DTC to display the freeze frame data.

(g) Check the freeze frame data for the output DTC.

Chassis > Air suspension

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

(Up&Down)G Sensor FR

Front acceleration sensor RH (up and down)

Min.: -1045.29 m/s2

Max.: 1045.26 m/s2

-0.98 to 0.98 m/s2 when stationary

The value changes when the vehicle (front RH) is bounced.

(Up&Down)G Sensor FL

Front acceleration sensor LH (up and down)

Min.: -1045.29 m/s2

Max.: 1045.26 m/s2

-0.98 to 0.98 m/s2 when stationary

The value changes when the vehicle (front LH) is bounced.

(Up&Down)G Sensor Rear

Rear acceleration sensor (up and down)

Min.: -1045.29 m/s2

Max.: 1045.26 m/s2

-0.98 to 0.98 m/s2 when stationary

The value changes when the vehicle (rear) is bounced.

IG Power Source Voltage

ECU power supply voltage

Min.: 0.0 V

Max.: 25.5 V

11 to 14 V (Actual ECU power supply voltage): Engine switch on (IG)

-

G Sensor Voltage

G sensor power supply voltage

Min.: 0.0 V

Max.: 25.5 V

4.8 to 5.2 V

-

ECU Substrate Temperature

Current ECU substrate temperature

Min.: 40°C

Max.: 120°C

Displays current ECU substrate temperature

-

FR Solenoid Aim Electric Current Level for Control

Target solenoid current value (front wheel RH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

FL Solenoid Aim Electric Current Level for Control

Target solenoid current value (front wheel LH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

RR Solenoid Aim Electric Current Level for Control

Target solenoid current value (rear wheel RH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

RL Solenoid Aim Electric Current Level for Control

Target solenoid current value (rear wheel LH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

FR Solenoid Electric Current

Solenoid current value (front wheel RH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

FL Solenoid Electric Current

Solenoid current value (front wheel LH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

RR Solenoid Electric Current

Solenoid current value (rear wheel RH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

RL Solenoid Electric Current

Solenoid current value (rear wheel LH)

Min.: 0 mA

Max.: 2040 mA

Changes depending on target damping force

-

Number of Trouble Codes

Number of DTCs stored

Min.: 0

Max.: 255

0

-

How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT

HINT:

  • Use the following procedure to troubleshoot the adaptive variable suspension system.
  • *: Use the Techstream.

PROCEDURE

1.

VEHICLE BROUGHT TO WORKSHOP
NEXT

2.

PROBLEM SYMPTOM CONFIRMATION
NEXT

3.

INSPECT BATTERY VOLTAGE

(a) Measure the voltage of the battery.

Standard Voltage:

11 to 14 V

If the voltage is below 11 V, recharge or replace the battery before proceeding.

NEXT

4.

CHECK ECUS CONNECTED TO CAN BUS*

(a) Check the ECUs connected to the CAN bus.

Click here

Result

Proceed to

No malfunction appears

A

Malfunction appears

B
B

GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING)

A

5.

CHECK DTC AND FREEZE FRAME DATA*

(a) Check for and write down any DTCs and Freeze Frame Data.

for DTC Check / Clear: Click here

for Freeze Frame Data: Click here

Chassis > Air suspension > Trouble Codes

(b) Clear the DTCs and Freeze Frame Data.

for DTC Check / Clear: Click here

for Freeze Frame Data: Click here

Chassis > Air suspension > Clear DTCs

(c) Recheck for DTCs.

Chassis > Air suspension > Trouble Codes

Result

Proceed to

DTCs are not output

A

DTCs are output

B
B

GO TO STEP 7

A

6.

OVERALL ANALYSIS AND TROUBLESHOOTING*

(a) Refer to Terminals of ECU.

Click here

(b) Refer to Data List / Active Test.

Click here

NEXT

GO TO STEP 8

7.

DIAGNOSTIC TROUBLE CODE CHART

(a) Proceed to Diagnostic Trouble Code Chart.

Click here

NEXT

8.

REPAIR OR REPLACE
NEXT

9.

CONFIRMATION TEST
NEXT

END

Parts Location

PARTS LOCATION

ILLUSTRATION

*1

FRONT ABSORBER CONTROL ACTUATOR RH (FRONT SHOCK ABSORBER ASSEMBLY RH)

*2

FRONT ABSORBER CONTROL ACTUATOR LH (FRONT SHOCK ABSORBER ASSEMBLY LH)

*3

REAR ABSORBER CONTROL ACTUATOR RH (REAR SHOCK ABSORBER ASSEMBLY RH)

*4

REAR ABSORBER CONTROL ACTUATOR LH (REAR SHOCK ABSORBER ASSEMBLY LH)

*5

FRONT SKID CONTROL SENSOR WIRE RH

*6

FRONT SKID CONTROL SENSOR WIRE LH

*7

SKID CONTROL SENSOR WIRE RH (NO. 1 PARKING BRAKE WIRE ASSEMBLY)

*8

SKID CONTROL SENSOR WIRE LH (NO. 2 PARKING BRAKE WIRE ASSEMBLY)

*9

ABSORBER CONTROL ECU

*10

SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY)

*11

ECM

*12

NO. 2 ENGINE ROOM RELAY BLOCK AND NO. 2 JUNCTION BLOCK ASSEMBLY

- IG1 NO. 3 RELAY

- AVS FUSE

ILLUSTRATION

*1

DRIVE MODE SELECT SWITCH (ELECTRIC PARKING BRAKE SWITCH ASSEMBLY)

*2

ACCELERATION SENSOR ASSEMBLY RH

*3

ACCELERATION SENSOR ASSEMBLY LH

*4

COMBINATION METER ASSEMBLY

*5

STEERING SENSOR

*6

DLC3

*7

AIRBAG ECU ASSEMBLY

*8

DRIVING SUPPORT ECU ASSEMBLY

*9

INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

- ECU-IG1 NO. 3 FUSE

-

-

Precaution

PRECAUTION

PRECAUTION FOR DISCONNECTING CABLE FROM NEGATIVE BATTERY TERMINAL

NOTICE:

When disconnecting the cable from the negative (-) battery terminal, initialize the following systems after the cable is reconnected.

System Name

See Procedure

Lane Departure Alert System (w/ Steering Control)

Intelligent Clearance Sonar System

Parking Assist Monitor System

Panoramic View Monitor System

Pre-collision System

Lighting System (for Gasoline Model with Cornering Light)

ADAPTIVE VARIABLE SUSPENSION SYSTEM PRECAUTION

NOTICE:

  • Performing work after replacing the absorber control ECU with a normally functioning one from another vehicle may result in DTCs being stored, or have a negative effect on other systems. When replacing the absorber control ECU, be sure to install a new one.
  • After replacing the absorber control ECU with a new one, perform registration of vehicle identification information.

    Click here

System Description

SYSTEM DESCRIPTION

ADAPTIVE VARIABLE SUSPENSION SYSTEM DESCRIPTION

(a) The ECM judges the mode based on the input from the drive mode select switch (electric parking brake switch assembly). The absorber control ECU receives the judgment result via CAN communication and controls the adaptive variable suspension.

System Diagram

SYSTEM DIAGRAM

Terminals Of Ecu

TERMINALS OF ECU

CHECK ABSORBER CONTROL ECU

(a) Measure the voltage and resistance according to the value(s) in the table below.

NOTICE:

Inspect the connectors from the back side while the connectors are connected.

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

K59-1 (IGB) - K59-4 (GND)

GR - W-B

IG power supply

Engine switch on (IG)

11 to 14 V

K59-4 (GND) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

K59-8 (CANH) - K59-7 (CANL)

B - W

CAN communication line

Engine switch off

54 to 69 Ω

K59-14 (SGB1) - K59-4 (GND)

R - W-B

Acceleration sensor RH power source

Engine switch on (IG)

4.75 to 5.25 V

K59-15 (SGB2) - K59-4 (GND)

SB - W-B

Acceleration sensor LH power source

Engine switch on (IG)

4.75 to 5.25 V

K59-22 (SGG1) - K59-4 (GND)

G - W-B

Acceleration sensor RH ground

Always

Below 1 Ω

K59-23 (SGS1) - K59-4 (GND)

L - W-B

Acceleration sensor RH signal input

Engine switch on (IG) with vehicle stationary

2.1 to 2.9 V

K59-24 (SGG2) - K59-4 (GND)

LG - W-B

Acceleration sensor LH ground

Always

Below 1 Ω

K59-25 (SGS2) - K59-4 (GND)

W - W-B

Acceleration sensor LH signal input

Engine switch on (IG) with vehicle stationary

2.1 to 2.9 V

Test Mode Procedure

TEST MODE PROCEDURE

TEST MODE PROCEDURE

NOTICE:

After replacing the absorber control ECU, it is necessary to perform registration of vehicle identification information. Vehicle identification information is automatically acquired when the system enters test mode.

HINT:

  • When entering test mode, the absorber control ECU stores all the test mode DTCs first. After completing the check for each test mode item, the test mode DTCs whose deletion conditions are met are cleared. The test mode DTCs for some items may not be cleared when only a certain signal is inspected.
  • When the system returns to normal mode, all the test mode DTCs will be cleared.

(a) Turn the engine switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the engine switch on (IG).

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / Air suspension / Utility / Signal Check.

Chassis > Air suspension > Utility

Tester Display

Signal Check

(f) Confirm that the system is in test mode by checking that the "Sport S+" indicator in the combination meter assembly is blinking at approximately 0.1-second intervals (0.1 seconds on and 0.1 seconds off).

HINT:

When vehicle identification information has not been acquired, the "Sport S+" indicator in the combination meter assembly blinks at approximately 1-second intervals (1 second on and 1 second off). After vehicle identification information is acquired, the "Sport S+" indicator in the combination meter assembly blinks at approximately 0.1-second intervals (0.1 seconds on and 0.1 seconds off).

(g) With the vehicle stationary on a level surface, wait for 1 second or more.

(h) Read the test mode DTCs by following the prompts on the Techstream screen.

(i) End test mode by following the prompts on the Techstream screen.

(j) Turn the engine switch off and disconnect the Techstream from the DLC3.

TEST MODE DTC CHART

(a) If a trouble code is output during the test mode DTC check, check the circuit listed for that code. For details of each code, refer to Link for the respective DTC in the chart.

DTC Code

Detection Item

Trouble Area

Deletion Condition

Link

C1796

(Up&Down)G Sensor FR
  • Acceleration sensor assembly RH
  • Wire harness or connector
  • Absorber control ECU

With the vehicle stationary on a level surface, an acceleration sensor value that is within -1.96 to 1.96 m/s2 is received from the acceleration sensor for 1 second or more.

C1797

(Up&Down)G Sensor FL
  • Acceleration sensor assembly LH
  • Wire harness or connector
  • Absorber control ECU

C1798

(Up&Down)G Sensor Rear

Absorber control ECU

Lost Communication With ECM/PCM "A" (U0100-U0122,U0124,U0126)

DESCRIPTION

The absorber control ECU receives signals from the ECM, skid control ECU (brake actuator assembly), airbag ECU assembly and steering sensor via CAN communication.

When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system first.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Memory

U0100

Lost Communication With ECM/PCM "A"

While driving at 30 km/h (19 mph) or more, data is not received via CAN communication for 3 seconds or more.
  • ECM
  • CAN communication system
  • Absorber control ECU

Does not come on

Yes

U0101

Lost Communication with TCM

While driving at 30 km/h (19 mph) or more, data is not received via CAN communication for 6 seconds or more.
  • ECM
  • CAN communication system
  • Absorber control ECU

Does not come on

Yes

U0122

Lost Communication With Vehicle Dynamics Control Module

Data is not received from the skid control ECU (brake actuator assembly) via CAN communication for 3 seconds or more.
  • Skid control ECU (brake actuator assembly)
  • CAN communication system
  • Absorber control ECU

Does not come on

Yes

U0124

Lost Communication with Lateral Acceleration Sensor Module

Data is not received from the airbag ECU assembly via CAN communication for 3 seconds or more.
  • Airbag ECU assembly
  • CAN communication system
  • Absorber control ECU

Does not come on

Yes

U0126

Lost Communication with Steering Angle Sensor Module

Data is not received from the steering sensor via CAN communication for 3 seconds or more.
  • Steering sensor
  • CAN communication system
  • Absorber control ECU

Does not come on

Yes

CAUTION / NOTICE / HINT

NOTICE:

  • Before performing troubleshooting, inspect the connectors of related circuits.
  • If DTC C1782 (Power Source Voltage Malfunction) is output at the same time, perform troubleshooting for C1782 first.

    Click here

  • Before replacing the absorber control ECU, perform all of the following:
    • Symptom simulation.

      Click here

    • DTC inspection.

      Click here

    • Techstream inspection.

      Click here

      • If no malfunctions are found in other areas, replace the absorber control ECU.
  • After replacing the absorber control ECU with a new one, perform registration of vehicle identification information.

    Click here

PROCEDURE

1.

CHECK FOR DTCS

(a) Clear the DTCs.

Click here

Chassis > Air suspension > Clear DTCs

(b) Turn the engine switch off.

(c) Drive the vehicle at a speed of 30 km/h (19 mph) or more for 10 seconds or more.

(d) Check for DTCs.

Click here

Chassis > Air suspension > Trouble Codes

Result

Proceed to

CAN DTCs are not output

A

CAN DTCs are output

B

HINT:

If a CAN communication malfunction DTC and a related sensor malfunction DTC are output at the same time, the CAN communication malfunction must be repaired before troubleshooting the sensor.

A

USE SIMULATION METHOD TO CHECK

B

GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING)

Absorber Control Switch

Front Acceleration Sensor

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