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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 Components

COMPONENTS ILLUSTRATION *1 NO. 2 PARKING BRAKE WIRE ASSEMBLY *2 REAR DISC BRAKE ANTI-SQUEAL SHIM KIT *3 REAR DISC BRAKE PAD *4 REAR DISC BRAKE CYLINDER ASSEMBLY *5 REAR NO. 1

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