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Home >> Infiniti >> 2023 >> QX55 Essential >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (DTC/Circuit Diagnosis) (1 Of 5) >> DTC/Circuit Diagnosis >> Power Supply And Ground Circuit >> VCR Control Module >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK FUSE 
    1. Turn ignition switch OFF.
    2. Pull out 15A fuse (No. 61) from IPDM E/R.
    3. Check that 15A fuse is not blowing.

    Is the fuse blown (open)?

    YES

    Replace the fuse after repairing the applicable circuit.

    NO

    GO TO 2.

  2. CHECK FUSE 
    1. Turn ignition switch OFF.
    2. Check that the following fuse is not blowing.

      Fuse No.

      Capacity

      #84

      20A

    Is the fuse blown (open)?

    YES

    Replace the fuse after repairing the applicable circuit.

    NO

    GO TO 3.

  3. CHECK GROUND CONNECTION 

    Check ground connection E15. Refer to Ground Inspection in Circuit Inspection .

    Is the inspection result normal?

    YES

    GO TO 4.

    NO

    Repair or replace error-detected parts.

  4. CHECK VCR CONTROL MODULE GROUND CIRCUIT 
    1. Disconnect VCR control module harness connectors.
    2. Check the continuity between VCR control module harness connector and ground.

      VCR control module

      --

      Continuity

      Connector

      Terminal

      F90

      1

      Ground

      Existed
    3. Also check harness for short to power.

    Is the inspection result normal?

    YES

    GO TO 5.

    NO

    Repair or replace error-detected parts.

  5. CHECK VCR CONTROL MODULE POWER SUPPLY 
    1. Reconnect VCR control module harness connectors.
    2. Check the voltage between VCR control module harness connector terminals as follows.

      VCR control module

      Voltage

      Connector

      +

      -

      Terminal

      F90

      5

      1

      Battery voltage

    Is the inspection result normal?

    YES

    GO TO 6.

    NO

    Perform trouble diagnosis for power supply circuit.

  6. CHECK IGNITION SWITCH SIGNAL 

    Check the voltage between VCR control module harness connectors as follows.

    VCR control module

    Condition

    Voltage

    +

    -

    Connector

    Terminal

    Terminal

    F90

    31

    1

    Ignition switch: ON

    Battery voltage

    Ignition switch: OFF

    0 V

    Is the inspection result normal?

    YES

    Check intermittent incident. Refer to Intermittent Incident .

    NO

    GO TO 7.

  7. CHECK IGNITION SWITCH SIGNAL 
    1. Turn ignition switch OFF.
    2. Disconnect VCR control module harness connectors.
    3. Disconnect IPDM E/R harness connector.
    4. Check the continuity between IPDM E/R harness connector and VCR control module harness connector.

      IPDM E/R

      VCR control module

      Continuity

      Connector

      Terminal

      Connector

      Terminal

      E121

      43

      F90

      31

      Existed
    5. Also check harness for short to power and short to ground.

    Is the inspection result normal?

    YES

    Perform trouble diagnosis for power supply circuit.

    NO

    Repair or replace error-detected parts.

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