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Home >> Infiniti >> 2018 >> QX80 RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostics) (2 Of 2) >> Component/Circuit Diagnosis >> EVAP Control System Pressure Sensor >> Component Function Check
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Component Function Check

  1. PERFORM COMPONENT FUNCTION CHECK 

    SYMBOL WITH GST

    1. Lift up drive wheels.
    2. Start engine (VDC switch OFF) and warm it up to normal operating temperature.
    3. Turn ignition switch OFF and wait at least 10 seconds.
    4. Start engine and wait at least 70 seconds.
    5. Set voltmeter probes to ECM harness connector terminals under the following conditions.

      ECM

      Connector

      +

      -

      Terminal

      Terminal

      E20

      121

      (EVAP control system pressure sensor signal)

      148

    6. Check EVAP control system pressure sensor value at idle speed and note it.
    7. Establish and maintain the following conditions for at least 1 minute.

      Air conditioner switch

      ON

      Headlamp switch

      ON

      Rear window defogger switch

      ON

      Engine speed

      Approx. 3, 000 RPM

      Gear position

      Any position other than P, N or R

    8. Verify that EVAP control system pressure sensor value stays 0.1 V less than the value at idle speed (measured at step 6) for at least 1 second.

    Is the inspection result normal?

    YES

    INSPECTION END

    NO

    Proceed to Diagnosis Procedure .