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Home >> Infiniti >> 2021 >> QX50 Essential, 4WD >> Repair and Diagnosis >> Steering >> Steering Control Systems >> Steering Control System (Direct Adaptive Steering) (2 Of 2) >> DTC/Circuit Diagnosis >> DTC C13BC-00: Control Module IGN Power Sup >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK IGNITION POWER SUPPLY FOR STEERING ANGLE MAIN CONTROL MODULE 
    1. Ignition switch OFF.
    2. Disconnect steering angle main control module harness connector.
    3. Check the voltage between steering angle main control module harness connector and ground.

      Steering angle main control module

      --

      Voltage (Approx.)

      Connector

      Terminal

      E149

      25

      Ground

      0 V
    4. Ignition switch ON.
    5. Check the voltage between steering angle control module harness connector and ground.

      Steering angle main control module

      --

      Voltage (Approx.)

      Connector

      Terminal

      E149

      25

      Ground

      Battery voltage

    Is the inspection result normal?

    YES

    GO TO 2.

    NO

    GO TO 3.

  2. CHECK INTERMITTENT INCIDENT FOR STEERING ANGLE MAIN CONTROL MODULE 
    1. Ignition switch OFF.
    2. Check enlarged contact spring of terminal. Refer to How to Check Terminal .
    3. Perform intermittent incident while turning steering wheel. Refer to Intermittent Incident .

    Is the inspection result normal?

    YES

    Replace steering angle main control module. Refer to Removal and Installation .

    NO

    Repair or replace malfunctioning component.

  3. CHECK IGNITION POWER SUPPLY CIRCUIT (1) 
    1. Ignition switch OFF.
    2. Disconnect steering angle sub control module harness connector.
    3. Check the continuity between steering angle main control module harness connector and steering angle sub control module harness connector.

      Steering angle main control module

      Steering angle sub control module

      Continuity

      Connector

      Terminal

      Connector

      Terminal

      E149

      25

      E144

      27

      Yes

    Is the inspection result normal?

    YES

    GO TO 4.

    NO

    Repair or replace malfunctioning component.

  4. CHECK INTERNAL CIRCUIT IN STEERING ANGLE SUB CONTROL MODULE 

    Check the continuity between steering angle sub control module connector terminals.

    Steering angle sub control module

    Continuity

    Terminal

    25

    27

    Yes

    Is the inspection result normal?

    YES

    GO TO 5.

    NO

    Replace steering angle sub control module. Refer to Removal and Installation .

  5. CHECK IGNITION POWER SUPPLY FOR STEERING ANGLE SUB CONTROL MODULE 
    1. Check the voltage between steering angle sub control module harness connector and ground.

      Steering angle sub control module

      --

      Voltage (Approx.)

      Connector

      Terminal

      E144

      25

      Ground

      0 V
    2. Ignition switch ON.
    3. Check the voltage between steering angle control module harness connector and ground.

      Steering angle sub control module

      --

      Voltage (Approx.)

      Connector

      Terminal

      E144

      25

      Ground

      Battery voltage

    Is the inspection result normal?

    YES

    GO TO 6.

    NO

    GO TO 7.

  6. CHECK INTERMITTENT INCIDENT FOR STEERING ANGLE SUB CONTROL MODULE 
    1. Ignition switch OFF.
    2. Check enlarged contact spring of terminal. Refer to How to Check Terminal .
    3. Perform intermittent incident while turning steering wheel. Refer to Intermittent Incident .

    Is the inspection result normal?

    YES

    Replace steering angle sub control module. Refer to Removal and Installation .

    NO

    Repair or replace malfunctioning component.

  7. CHECK IGNITION POWER SUPPLY CIRCUIT (2) 
    1. Ignition switch OFF.
    2. Disconnect steering force control module harness connector.
    3. Check the continuity between steering angle sub control module harness connector and steering force control module harness connector.

      Steering angle sub control module

      Steering force control module

      Continuity

      Connector

      Terminal

      Connector

      Terminal

      E144

      25

      E141

      27

      Yes

    Is the inspection result normal?

    YES

    GO TO 8.

    NO

    Repair or replace malfunctioning component.

  8. CHECK INTERNAL CIRCUIT IN STEERING FORCE CONTROL MODULE 

    Check the continuity between steering force control module connector terminals.

    Steering force control module

    Continuity

    Terminal

    25

    27

    Yes

    Is the inspection result normal?

    YES

    GO TO 9.

    NO

    Replace steering force control module. Refer to Removal and Installation .

  9. CHECK IGNITION POWER SUPPLY FOR STEERING FORCE CONTROL MODULE 
    1. Check the voltage between steering force control module harness connector and ground.

      Steering force control module

      --

      Voltage (Approx.)

      Connector

      Terminal

      E141

      25

      Ground

      0 V
    2. Ignition switch ON.
    3. Check the voltage between force control module harness connector and ground.

      Steering force control module

      --

      Voltage (Approx.)

      Connector

      Terminal

      E141

      25

      Ground

      Battery voltage

    Is the inspection result normal?

    YES

    GO TO 10.

    NO

    GO TO 11.

  10. CHECK INTERMITTENT INCIDENT FOR STEERING FORCE CONTROL MODULE 
    1. Ignition switch OFF.
    2. Check enlarged contact spring of terminal. Refer to How to Check Terminal .
    3. Perform intermittent incident while turning steering wheel. Refer to Intermittent Incident .

    Is the inspection result normal?

    YES

    Replace steering force control module. Refer to Removal and Installation .

    NO

    Repair or replace malfunctioning component.

  11. CHECK IGNITION POWER SUPPLY CIRCUIT (3) 
    1. Ignition switch OFF.
    2. Check the 10 A fuse (No. 53).
    3. Check the harness for open or short between steering force control module harness connector E141 terminal 25 and the 10 A fuse (No. 53).

    Is the inspection result normal?

    YES

    Perform the trouble diagnosis for ignition power supply circuit. Refer to appropriate system wiring diagram.

    NO

    Repair or replace malfunctioning component.

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