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Home >> Infiniti >> 2022 >> Q50 Sensory, AWD >> Repair and Diagnosis >> Steering >> Steering Control Systems >> Steering Control System (Diagnostics) >> Component/Circuit Diagnosis >> Power Supply And Ground Circuit (Steering Force Control Module) >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK STEERING FORCE CONTROL MODULE GROUND CIRCUIT 
    1. Turn the ignition switch OFF.
    2. Disconnect steering force control module harness connector.
    3. Check the continuity between control module harness connector and ground.

      Steering force control module

      --

      Continuity

      Connector

      Terminal

      M72

      33

      Ground

      Existed

    Is the inspection result normal?

    YES

    GO TO 2.

    NO

    Repair open circuit in harness or connectors.

  2. CHECK STEERING ANGLE MAIN CONTROL MODULE GROUND CIRCUIT 
    1. Disconnect steering angle main control module harness connector.
    2. Check the continuity between control module harness connector and ground.

      Steering angle main control module

      --

      Continuity

      Connector

      Terminal

      E27

      33

      Ground

      Existed

      E28

      39

    Is the inspection result normal?

    YES

    GO TO 3.

    NO

    Repair open circuit in harness or connectors.

  3. CHECK STEERING ANGLE SUB CONTROL MODULE GROUND CIRCUIT 
    1. Disconnect steering angle sub control module harness connector.
    2. Check the continuity between control module harness connector and ground.

      Steering angle sub control module

      --

      Continuity

      Connector

      Terminal

      E30

      33

      Ground

      Existed

      E31

      39

    Is the inspection result normal?

    YES

    GO TO 4.

    NO

    Repair open circuit in harness or connectors.

  4. CHECK STEERING FORCE CONTROL MODULE POWER SUPPLY CIRCUIT (1) 
    1. Disconnect steering force control module harness connector.
    2. Check the voltage between steering force control module harness connector and ground.

      +

      --

      Voltage

      Steering force control module

      Connector

      Terminal

      M72

      34

      Ground

      10.5 - 16.0 V

    Is the inspection result normal?

    YES

    GO TO 6.

    NO

    GO TO 5.

  5. CHECK STEERING FORCE CONTROL MODULE POWER SUPPLY CIRCUIT (2) 
    1. Check the 60 A fusible link (No. G). (With pre-crash seat belt system)
    2. Check the 60 A fusible link (No. I). (Without pre-crash seat belt system)
    3. Check the harness for open or short between steering force control module harness connector No. 34 terminal and the 60 A fusible link (No. G). (With pre-crash seat belt system)
    4. Check the harness for open or short between steering angle sub control module harness connector No. 34 terminal and the 60 A fusible link (No. I). (Without pre-crash seat belt system)

    Is the inspection result normal?

    YES

    Perform the trouble diagnosis for 12 V battery power supply circuit.

    NO

    Repair / replace harness, connector, or fusible link.

  6. CHECK STEERING ANGLE MAIN CONTROL MODULE POWER SUPPLY CIRCUIT (1) 
    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

      E27

      34

      Ground

      10.5 - 16.0 V

    Is the inspection result normal?

    YES

    GO TO 8.

    NO

    GO TO 7.

  7. CHECK STEERING ANGLE MAIN CONTROL MODULE POWER SUPPLY CIRCUIT (2) 
    1. Check the 100 A fusible link (No. J).
    2. Check the harness for open or short between steering angle main control module harness connector No. 34 terminal and the 100 A fusible link (No. J).

    Is the inspection result normal?

    YES

    Perform the trouble diagnosis for 12 V battery power supply circuit.

    NO

    Repair / replace harness, connector, or fusible link.

  8. CHECK STEERING ANGLE SUB CONTROL MODULE POWER SUPPLY CIRCUIT (1) 
    1. Turn the ignition switch OFF.
    2. Disconnect steering angle sub control module harness connector.
    3. Check the voltage between steering angle sub control module harness connector and ground.

      +

      --

      Voltage

      Steering angle sub control module

      Connector

      Terminal

      E30

      34

      Ground

      10.5 - 16.0 V

    Is the inspection result normal?

    YES

    GO TO 10.

    NO

    GO TO 9.

  9. CHECK STEERING ANGLE SUB CONTROL MODULE POWER SUPPLY CIRCUIT (2) 
    1. Check the 100 A fusible link (No. H). (With pre-crash seat belt system)
    2. Check the 100 A fusible link (No. K). (Without pre-crash seat belt system)
    3. Check the harness for open or short between steering angle sub control module harness connector No. 34 terminal and the 100 A fusible link (No. H). (With pre-crash seat belt system)
    4. Check the harness for open or short between steering angle sub control module harness connector No. 34 terminal and the 100 A fusible link (No. K). (Without pre-crash seat belt system)

    Is the inspection result normal?

    YES

    Perform the trouble diagnosis for 12 V battery power supply circuit.

    NO

    Repair / replace harness, connector, or fusible link.

  10. 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 main 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

    INSPECTION END

    NO

    GO TO 11.

  11. 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 12.

    NO

    Repair / replace harness or connector.

  12. 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 13.

    NO

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

  13. 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 sub 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

    • Check enlarged contact spring of terminal. Refer to Inspection .
    • Perform intermittent incident while turning steering wheel. Refer to Inspection .

    NO

    GO TO 14.

  14. 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 15.

    NO

    Repair / replace harness or connector.

  15. 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 16.

    NO

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

  16. 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

    • Check enlarged contact spring of terminal. Refer to Inspection .
    • Perform intermittent incident while turning steering wheel. Refer to Inspection .

    NO

    GO TO 17.

  17. CHECK IGNITION POWER SUPPLY CIRCUIT (3) 
    1. Turn the ignition switch OFF.
    2. Check the 10 A fuse (No. 12).
    3. Disconnect fuse block (J/B) harness connector.
    4. Check the continuity between steering force control module connector and fuse block (J/B).

      Steering force control module

      Fuse block (J/B)

      Continuity

      Connector

      Terminal

      Connector

      Terminal

      M71

      25

      M133

      20C

      Existed
    5. Check the continuity between steering force control module connector and ground.

      Steering force control module

      --

      Continuity

      Connector

      Terminal

      M71

      25

      Ground

      Not existed

    Is the inspection result normal?

    YES

    Perform the trouble diagnosis for ignition power supply circuit.

    NO

    Repair / replace harness, connector, or fuse.

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