Lexus NX manuals

Lexus NX: Suspension Control ECU Malfunction (C1781)

Lexus NX 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

C1781

Suspension Control ECU Malfunction

Either condition 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

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.

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  • Before replacing the absorber control ECU, perform all of the following again: 1) symptom simulation ; 2) DTC inspection ; and 3) Techstream inspection (ECU Data List or Active Test ). If no malfunctions are found in other areas, replace the absorber control ECU.
  • When the absorber control ECU is replaced, switch to test mode and check that all test mode DTCs are cleared when their respective deletion conditions are met.

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PROCEDURE

1.

CHECK FOR DTC (CAN COMMUNICATION SYSTEM)

(a) Check for DTCs.

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Chassis > Air suspension > Trouble Codes

Result

Proceed to

CAN DTC is not output

A

CAN DTC is output

B
A

REPLACE ABSORBER CONTROL ECU

B

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

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