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Home >> Infiniti >> 2024 >> Q50 Luxe, AWD >> Repair and Diagnosis >> Steering >> Steering Control Systems >> Steering Control System (DTCS) (2 Of 2) >> EPS/DAST 3 (Power Steering Control Module) >> U140E Chassis Control Module >> DTC Diagnosis Procedure
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DTC Diagnosis Procedure

  1. PERFORM CHASSIS CONTROL MODULE SELF-DIAGNOSIS 

    SYMBOL With CONSULT

    1. Turn the ignition switch OFF to ON.
    2. Perform "CHASSIS CONTROL" self-diagnosis. Refer to Diagnosis Description .

    Is any DTC detected?

    YES>>

    Check the DTC. Refer to DTC Index .

    NO>>

    GO TO 2.

  2. CHECK CONNECTOR AND TERMINAL 
    1. Turn the ignition switch OFF.
    2. Disconnect chassis control module harness connector.
    3. Disconnect power steering control module harness connector.
    4. Check the connector for disconnection or looseness.
    5. Check the pin terminals for damage or loose connection with harness connector.

    Is the inspection result normal?

    YES>>

    GO TO 3.

    NO>>

    Repair or replace harness, connector, or terminal, securely lock the connector.

  3. PERFORM SELF-DIAGNOSIS 

    SYMBOL With CONSULT

    1. Connect chassis control module harness connector.
    2. Connect power steering control module harness connector.
    3. Turn the ignition switch OFF to ON.
    4. Erase self-diagnostic results for "EPS/DAST 3".
    5. Turn the ignition switch OFF and wait for at least 10 seconds.
    6. Turn the ignition switch OFF to ON.
    7. Perform self-diagnosis for "EPS/DAST 3".

    Is DTC "U140E" detected?

    YES>>

    Power steering control module is malfunctioning. Replace steering gear assembly. Refer to STEERING GEAR AND LINKAGE : Removal and Installation .

    NO>>

    Check pin terminal and connection of each harness connector for malfunctioning conditions.