Mike's Workshop Manuals: Service manuals for every vehicle
Home >> Infiniti >> 2021 >> QX80 Premium Select, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTCS) (1 Of 5) >> Engine (ECM) >> DTC P0090: Fuel Rail Pressure Control System >> DTC Diagnosis Procedure

DTC Diagnosis Procedure

  1. CHECK HIGH PRESSURE FUEL PUMP CIRCUIT 
    1. Turn ignition switch ON.
    2. Disconnect ECM harness connector and high pressure fuel pump harness connector.
    3. Check the continuity between ECM harness connector and high pressure fuel pump harness connector.

      +

      -

      Value

      (Approx.)

      ECM

      High pressure fuel pump

      Connector

      Terminal

      Connector

      Terminal

      F92

      59

      F24

      1

      Existed

      60

      2

    4. Also check harness for short to ground and to power.

    Is inspection result normal?

    YES

    GO TO 2.

    NO

    Repair or replace the error-detected parts.

  2. CHECK HIGH PRESSURE FUEL PUMP 

    Check high pressure fuel pump. Refer to Component Inspection .

    Is inspection result normal?

    YES

    Check intermittent incident. Refer to Inspection .

    NO

    Replace the error-detected parts.