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Home >> Jeep >> 2021 >> Grand Cherokee Trackhawk >> Repair and Diagnosis >> Engine Performance >> System >> 6.2L - DTCS P0443 To P0688 >> DTC Troubleshooting >> P062A-Fuel Pump Control Performance >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    NOTE:

    If there are any Fuel Pressure Sensor or Fuel Pump Control Module DTCs present, repair those DTCs before proceeding with this test.

    1. Turn the ignition on.
    2. With the scan tool, read DTCs and record on the repair order.

      Is the DTC active or pending?

      Yes 

      • Go To  2

      No 

  2. CHECK THE FUEL SYSTEM FOR LEAKS 
    1. Visually inspect the fuel system for signs of a fuel leak.

      Were any fuel leaks found in the system?

      Yes 

      No 

      • Go To  3
  3. CHECK THE FUEL SYSTEM PRESSURE 
    1. Perform the diagnostic procedure for CHECKING THE FUEL DELIVERY SYSTEM. Refer to CHECKING THE FUEL DELIVERY SYSTEM (HARD START) .

      Were any problems found with the fuel delivery system?

      Yes 

      No 

      • Go To  4
  4. CHECK FOR HIGH RESISTANCE IN THE (K181) FUEL RAIL PRESSURE SENSOR SIGNAL CIRCUIT 
    1. Turn the ignition off.
    2. Disconnect the FRPS harness connector.
    3. Disconnect both PCM C1 and C2 harness connectors.
    4. Measure the resistance of the (K181) FRPS Signal circuit between the FRPS harness connector and the PCM C1 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  5

      No 

      • Repair the (K181) FRPS Signal circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  5. CHECK FOR HIGH RESISTANCE IN THE (K900) SENSOR GROUND CIRCUIT 
    1. Measure the resistance of the (K900) Sensor Ground circuit between the FRPS harness connector and the PCM C1 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  6

      No 

      • Repair the (K900) Sensor Ground circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  6. CHECK FOR HIGH RESISTANCE IN THE (K859) 5-VOLT SUPPLY CIRCUIT 
    1. Measure the resistance of the (K859) 5-Volt Supply circuit between the FRPS harness connector and the PCM C2 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  7

      No 

      • Repair the (K859) 5-Volt Supply Ground circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  7. CHECK THE FUEL RAIL PRESSURE SENSOR 
    1. Turn the ignition off.
    2. Reconnect both PCM C1 and C2 harness connectors.
    3. Turn the ignition on.
    4. With the scan tool, read DTCs.
    5. While monitoring scan tool, connect a jumper between the (K181) FRPS Signal circuit and the (K900) Sensor Ground circuit at the FRPS harness connector.
      NOTE:

      The PCM should display the P018D-FUEL PRESSURE SENSOR HIGH DTC with the connector unplugged and P018C-FUEL PRESSURE SENSOR LOW DTC with the jumper in place.

      Does the scan tool display the DTCs as described above?

      Yes 

      • Replace the Fuel Rail Pressure Sensor in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No