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Diagnostic Test

WARNING: This page is about a different car, the 2005 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
  1. 1)  FUEL PUMP RELAY OPERATION 

    Ignition on, engine not running.

    With a scan tool, actuate the Fuel Pump Relay.

    Is the Fuel Pump Relay operating? 

    Yes 

    1. Refer to INTERMITTENT CONDITION .
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To step  2).
  2. 2)  FUEL PUMP RELAY 

    Turn the ignition off.

    Remove the Fuel Pump Relay from the IPM.

    Measure the resistance of the Fuel Pump Relay Coil.

    Is the resistance between 70 to 90 ohms? 

    Yes 

    1. Go To step  3).

    No 

    1. Replace the Fuel Pump Relay.
    2. Perform POWERTRAIN VERIFICATION TEST .
  3. 3)  (A916) FUSED B+ CIRCUIT 

    Ignition on, engine not running.

    Using a 12-volt test light connected to ground, probe the (A916) Fused B+ circuit.

    Does the test light illuminate brightly? 

    Yes 

    1. Go To step  4).

    No 

    1. Repair the open or short to ground in the (A916) Fused B+ circuit. Inspect the related fuse and repair as necessary.
    2. Perform POWERTRAIN VERIFICATION TEST .
  4. 4)  (F942) FUSED IGNITION SWITCH OUTPUT CIRCUIT 

    Ignition on, engine not running.

    Using a 12-volt test light connected to ground, probe the (F942) Fused Ignition Switch Output circuit.

    Does the test light illuminate brightly? 

    Yes 

    1. Go To step  5).

    No 

    1. Repair the open or short to ground in the (F942) Fused Ignition Switch Output circuit. Inspect the related fuse and repair as necessary.
    2. Perform POWERTRAIN VERIFICATION TEST .
  5. 5)  (K31) CONTROL CIRCUIT OPEN 

    Turn the ignition off.

    Disconnect the C3 PCM harness connector.

    CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

    Measure the resistance of the (K31) Fuel Pump Relay Control circuit from the IPM to the appropriate terminal of special tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go To step  6).

    No 

    1. Repair the open in the (K31) Fuel Pump Relay Control circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  6. 6)  (K31) CONTROL CIRCUIT SHORTED TO GROUND  

    Measure the resistance between ground and the (K31) Fuel Pump Relay Control circuit in the IPM.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the short to ground in the (K31) Fuel Pump Relay Control circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To step  7).
  7. 7)  PCM 
    NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

    Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.

    Were there any problems found? 

    Yes 

    1. Repair as necessary.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Replace and program the Powertrain Control Module per Service Information.
    2. Perform POWERTRAIN VERIFICATION TEST .
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