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Home >> Infiniti >> 2019 >> QX50 Essential, FWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (DTC/Circuit Diagnosis) (4 Of 12) >> DTC/Circuit Diagnosis >> DTC P0191: FRP Sensor >> Component Inspection
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Component Inspection

  1. CHECK FUEL RAIL PRESSURE (FRP) SENSOR 

    SYMBOL With CONSULT

    1. Turn ignition switch OFF.
    2. Reconnect harness connector disconnected.
    3. Start engine and warm it up to normal operating temperature.
    4. Select "FUEL PRES SEN V" in "DATA MONITOR" mode of "ENGINE" using CONSULT and check the indication under the following condition.

      Monitor item

      Condition

      Indication

      FUEL PRES SEN V

      • Engine: After warming up
      • Selector lever: P or N position
      • A/C switch: OFF
      • No load

      Engine speed: Idle

      0.820 - 1.140 V

      Revving engine from idle to 4, 000 rpm quickly

      0.820 - 2.900 V

    SYMBOL Without CONSULT

    1. Turn ignition switch OFF.
    2. Reconnect harness connector disconnected.
    3. Start engine and warm it up to normal operating temperature.
    4. Check FRP sensor signal voltage.

      ECM

      Condition

      Voltage

      Connector

      +

      -

      Terminal

      F51

      44

      45

      [Engine is running]

      • Engine warm-up condition
      • Engine speed: Idle

      0.82 - 1.14 V

      [Engine is running]

      • Engine warm-up condition
      • Revving engine from idle to 4, 000 rpm quickly

      0.82 - 2.9 V

    Is inspection result normal?

    YES

    INSPECTION END

    NO

    Replace FRP sensor. Refer to Exploded View .