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Home >> Infiniti >> 2021 >> QX50 Essential, 4WD >> Repair and Diagnosis >> Accessories & Equipment >> Drivers Assistance Systems - ADAS >> ADAS Control Unit (DTC/Circuit Diagnosis) (1 Of 2) >> DTC C1A15: Gear Position >> ADAS Control Unit >> With Direct Adaptive Steering System >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK DTC PRIORITY 

    If DTC "C1A15-00" is displayed with DTC "U1000-01" or "C1A03-00", or "C1A04-00" first diagnose the DTC "U1000-01", "C1A03-00", or "C1A04-00"

    Is applicable DTC detected?

    YES

    Perform diagnosis of applicable.

    NO

    GO TO 2.

  2. CHECK VEHICLE SPEED SIGNAL 

    Check that "VHCL SPEED SE" operates normally in "DATA MONITOR" of "ICC/ADAS".

    CAUTION: Be careful of the vehicle speed.

    Is the inspection result normal?

    YES

    GO TO 3.

    NO

    GO TO 7.

  3. CHECK GEAR POSITION 

    Check that "GEAR" operates normally in "DATA MONITOR" of "ICC/ADAS".

    CAUTION: Be careful of the vehicle speed.

    Is the inspection result normal?

    YES

    GO TO 5.

    NO

    GO TO 4.

  4. CHECK GEAR POSITION SIGNAL 

    Check that "GEAR" operates normally in "DATA MONITOR" of "TRANSMISSION".

    Is the inspection result normal?

    YES

    GO TO 5.

    NO

    GO TO 6.

  5. CHECK INPUT SPEED SENSOR SIGNAL 

    Check that "INPUT SPEED" operates normally in "DATA MONITOR" of "TRANSMISSION".

    Is the inspection result normal?

    YES

    Replace the ADAS control unit. Refer to Removal and Installation .

    NO

    GO TO 6.

  6. CHECK TCM SELF-DIAGNOSIS RESULTS 
    1. Perform "All DTC Reading".
    2. Check if any DTC is detected in "Self Diagnostic Result" of "TRANSMISSION".

    Is any DTC detected?

    YES

    Perform diagnosis on the detected DTC and repair or replace the malfunctioning parts. Refer to DTC Index .

    NO

    Replace the ADAS control unit. Refer to Removal and Installation .

  7. CHECK ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF-DIAGNOSIS RESULTS 
    1. Perform "All DTC Reading".
    2. Check if any DTC is detected in "Self Diagnostic Result" of "ABS".

    Is any DTC detected?

    YES

    Perform diagnosis on the detected DTC and repair or replace the malfunctioning parts. Refer to DTC Index .

    NO

    Replace the ADAS control unit. Refer to Removal and Installation .