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Home >> Infiniti >> 2021 >> Q50 Pure, AWD >> Repair and Diagnosis (Single Page) >> Steering >> Steering Control Systems >> Steering Control System (DTCS) (1 Of 2) >> EPS/DAST 3 (Steering Force Control Module) >> DTC C13BC-00: Control Module IGN Power Sup >> DTC Diagnosis Procedure
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DTC Diagnosis Procedure

  1. CHECK IGNITION POWER SUPPLY FOR STEERING ANGLE MAIN CONTROL MODULE 
    1. Turn the 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.

      +

      --

      Voltage

      Steering angle main control module

      Connector

      Terminal

      E26

      25

      Ground

      Approx. 0 V

    4. Turn the ignition switch ON.
    5. Check the voltage between steering angle control module harness connector and ground.

      +

      --

      Voltage

      Steering angle main control module

      Connector

      Terminal

      E26

      25

      Ground

      10.5 - 16.0 V

    Is the inspection result normal?

    YES

    GO TO 2.

    NO

    GO TO 3.

  2. CHECK INTERMITTENT INCIDENT FOR STEERING ANGLE MAIN CONTROL MODULE 
    1. Turn the ignition switch OFF.
    2. Check enlarged contact spring of terminal. Refer to Inspection .
    3. Perform intermittent incident while turning steering wheel. Refer to Inspection .

    Is the inspection result normal?

    YES

    Replace steering angle main control module. Refer to STEERING ANGLE MAIN CONTROL MODULE : Removal & Installation .

    NO

    Repair or replace error-detected part.

  3. CHECK IGNITION POWER SUPPLY CIRCUIT (1) 
    1. Turn the 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

      E26

      25

      E29

      27

      Existed

    Is the inspection result normal?

    YES

    GO TO 4.

    NO

    Repair or replace error-detected parts.

  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

    Existed

    Is the inspection result normal?

    YES

    GO TO 5.

    NO

    Replace steering angle sub control module. Refer to STEERING ANGLE SUB CONTROL MODULE : Removal & 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.

      +

      --

      Voltage

      Steering angle sub control module

      Connector

      Terminal

      E29

      25

      Ground

      Approx. 0 V

    2. Turn the ignition switch ON.
    3. Check the voltage between steering angle control module harness connector and ground.

      +

      --

      Voltage

      Steering angle sub control module

      Connector

      Terminal

      E29

      25

      Ground

      10.5 - 16.0 V

    Is the inspection result normal?

    YES

    GO TO 6.

    NO

    GO TO 7.

  6. CHECK INTERMITTENT INCIDENT FOR STEERING ANGLE SUB CONTROL MODULE 
    1. Turn the ignition switch OFF.
    2. Check enlarged contact spring of terminal. Refer to Inspection .
    3. Perform intermittent incident while turning steering wheel. Refer to Inspection .

    Is the inspection result normal?

    YES

    Replace steering angle sub control module. Refer to STEERING ANGLE SUB CONTROL MODULE : Removal & Installation .

    NO

    Repair or replace error-detected part.

  7. CHECK IGNITION POWER SUPPLY CIRCUIT (2) 
    1. Turn the 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

      E29

      25

      M71

      27

      Existed

    Is the inspection result normal?

    YES

    GO TO 8.

    NO

    Repair or replace error-detected parts.

  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

    Existed

    Is the inspection result normal?

    YES

    GO TO 9.

    NO

    Replace steering force control module. Refer to STEERING FORCE CONTROL MODULE : Removal & Installation .

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

      +

      --

      Voltage

      Steering force control module

      Connector

      Terminal

      M71

      25

      Ground

      Approx. 0 V

    2. Turn the ignition switch ON.
    3. Check the voltage between force control module harness connector and ground.

      +

      --

      Voltage

      Steering force control module

      Connector

      Terminal

      M71

      25

      Ground

      10.5 - 16.0 V

    Is the inspection result normal?

    YES

    GO TO 10.

    NO

    GO TO 11.

  10. CHECK INTERMITTENT INCIDENT FOR STEERING FORCE CONTROL MODULE 
    1. Turn the ignition switch OFF.
    2. Check enlarged contact spring of terminal. Refer to Inspection .
    3. Perform intermittent incident while turning steering wheel. Refer to Inspection .

    Is the inspection result normal?

    YES

    Replace steering force control module. Refer to STEERING FORCE CONTROL MODULE : Removal & Installation .

    NO

    Repair or replace error-detected part.

  11. CHECK IGNITION POWER SUPPLY CIRCUIT (3) 
    1. Turn the ignition switch OFF.
    2. Check the 10 A fuse (No. 12).
    3. Check the harness for open or short between steering force control module harness connector No. 25 terminal and the 10 A fuse (No. 12).

    Is the inspection result normal?

    YES

    Perform the trouble diagnosis for ignition power supply circuit.

    NO

    Repair or replace error-detected parts.