Lexus ES manuals

Lexus ES: Suspension Control ECU Malfunction (C1781)

Lexus ES (XZ10) Service Manual / Suspension / Suspension Control / Adaptive Variable Suspension System / 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.
  • 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)

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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 C

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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

SEE MORE:

 Removal

REMOVAL PROCEDURE 1. REMOVE FRONT DOOR SCUFF PLATE LH Click here 2. REMOVE COWL SIDE TRIM BOARD LH Click here 3. REMOVE FRONT DOOR OPENING TRIM COVER LH Click here 4. REMOVE INSTRUMENT SIDE PANEL LH Click here 5. REMOVE NO. 1 INSTRUMENT PANEL UNDER COVER SUB-ASSEMBLY Click here 6. REM

 Precaution

PRECAUTION PRECAUTION FOR DISCONNECTING CABLE FROM NEGATIVE BATTERY TERMINAL NOTICE: When disconnecting the cable from the negative (-) battery terminal, initialize the following system(s) after the cable is reconnected: System See Procedure Lane Control System (for Gasoline Model)

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