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Diagnostic Test

  1. 1) FUEL LEVEL SENSOR VOLTAGE ABOVE 4.9 VOLTS 

    Ignition on, engine not running.

    With the scan tool, read the Fuel Level Sensor voltage.

    Is the Fuel Level Sensor voltage above 4.9 volts? 

    Yes 

    1. Go To step  2).

    No 

    1. Refer to INTERMITTENT CONDITION .
    2. Perform POWERTRAIN VERIFICATION TEST .
  2. 2) FUEL LEVEL SENSOR 

    Turn the ignition off.

    Disconnect the Fuel Pump Module electrical harness connector.

    Connect a jumper wire between the (N4) Fuel Level Signal circuit and the (K900) Sensor ground circuit at the Fuel Pump Module harness connector.

    Ignition on, engine not running.

    With the scan tool, read the Fuel Level Sensor voltage.

    NOTE: Remove the jumper wire before continuing.

    Did the Fuel Level Sensor voltage change from above 4.8 volts to below 0.4 of a volt? 

    Yes 

    1. Replace the Fuel Level Sensor.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To step  3).
  3. 3) DETERMINE VEHICLE ENGINE TYPE 

    What type of engine is the vehicle equipped with? 

    Gas 

    1. Go To step  4).

    Gas (ESP) 

    1. Go To step  8).

    Diesel 

    1. Go To step  12).
  4. 4) (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO VOLTAGE 
    Fig 1: Measuring Voltage On Fuel Level Signal Circuit
    GC0046859Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the C2 and C3 PCM harness connectors.

    WARNING: When the engine is operating, do not stand in a direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing.

    Ignition on, engine not running.

    Measure the voltage on the (N4) Fuel Level Signal circuit at the Fuel Pump Module harness connector.

    Is the voltage above 5.3 volts? 

    Yes 

    1. Repair the short to voltage in the (N4) Fuel Level Signal circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To step  5).
  5. 5) (N4) FUEL LEVEL SIGNAL CIRCUIT OPEN 
    Fig 2: Measuring Resistance Of Fuel Level Signal Circuit
    GC0046860Courtesy of CHRYSLER LLC

    Turn the ignition off.

    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 (N4) Fuel Level Signal circuit from the Fuel Pump Module harness connector to the appropriate terminal in Miller Special Tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go To step  6).

    No 

    1. Repair the open in the (N4) Fuel Level Signal circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  6. 6) (K900) SENSOR GROUND CIRCUIT OPEN 
    Fig 3: Measuring Resistance Of Sensor Ground Circuit
    GC0046861Courtesy of CHRYSLER LLC
    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 (K900) Sensor ground circuit from the Fuel Pump Module harness connector to the appropriate terminal of special tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go To step  7).

    No 

    1. Repair the open in the (K900) Sensor ground circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  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.

    If there are no possible causes remaining, view repair. 

    Repair 

    1. Replace and program the Powertrain Control Module per Service Information.
    2. Perform POWERTRAIN VERIFICATION TEST .
  8. 8) (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED BATTERY TO VOLTAGE 
    Fig 4: Measuring Voltage On Fuel Level Signal Circuit
    GC0046862Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the BCM C2 harness connectors.

    Ignition on, engine not running.

    Measure the voltage on the (N4) Fuel Level Signal circuit at the Fuel Pump Module harness connector.

    Is the voltage above 5.3 volts? 

    Yes 

    1. Repair the short to voltage in the (N4) Fuel Level Signal circuit.
    2. Perform BODY VERIFICATION TEST .

    No 

    1. Go To step  9).
  9. 9) (N4) FUEL LEVEL SIGNAL CIRCUIT OPEN 
    Fig 5: Measuring Resistance Of Fuel Level Signal Circuit
    GC0046863Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Measure the resistance of the (N4) Fuel Level Signal circuit from the Fuel Pump Module harness connector to the appropriate terminal in Miller Special Tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go To step  10).

    No 

    1. Repair the open in the (N4) Fuel Level Signal circuit.
    2. Perform BODY VERIFICATION TEST .
  10. 10) (K310) SENSOR GROUND CIRCUIT OPEN 
    Fig 6: Measuring Resistance Of Sensor Ground Circuit
    GC0046864Courtesy of CHRYSLER LLC

    Measure the resistance of the (K310) Sensor ground circuit from the Fuel Pump Module harness connector to the appropriate terminal of Miller Special Tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go To step  11).

    No 

    1. Repair the open in the (K310) Sensor ground circuit.
    2. Perform BODY VERIFICATION TEST .
  11. 11) BCM 
    NOTE: Before continuing, check the BCM 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.

    If there are no possible causes remaining, view repair. 

    Repair 

    1. Replace and program the Body Control Module per Service Information.
    2. Perform BODY VERIFICATION TEST .
  12. 12) (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO VOLTAGE 
    Fig 7: Measuring Voltage On Fuel Level Signal Circuit
    GC0046865Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the BCM C2 harness connectors.

    Ignition on, engine not running.

    Measure the voltage on the (N4) Fuel Level Signal circuit at the Fuel Pump Module harness connector.

    Is the voltage above 5.3 volts? 

    Yes 

    1. Repair the short to voltage in the (N4) Fuel Level Signal circuit.
    2. Perform BODY VERIFICATION TEST .

    No 

    1. Go To step  13).
  13. 13) (K304) FUEL LEVEL SIGNAL CIRCUIT OPEN 
    Fig 8: Measuring Resistance Of Fuel Level Signal Circuit
    GC0046866Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Measure the resistance of the (K304) Fuel Level Signal circuit from the Fuel Pump Module harness connector to the appropriate terminal in Miller Special Tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go To step  14).

    No 

    1. Repair the open in the (K304) Fuel Level Signal circuit.
    2. Perform BODY VERIFICATION TEST .
  14. 14) (K300) SENSOR GROUND CIRCUIT OPEN 
    Fig 9: Measuring Resistance Of Sensor Ground Circuit
    GC0046867Courtesy of CHRYSLER LLC

    Measure the resistance of the (K300) Sensor ground circuit from the Fuel Pump Module harness connector to the appropriate terminal of Miller Special Tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go To step  15).

    No 

    1. Repair the open in the (K300) Sensor ground circuit.
    2. Perform BODY VERIFICATION TEST .
  15. 15) BCM 
    NOTE: Before continuing, check the BCM 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.

    If there are no possible causes remaining, view repair. 

    Repair 

    1. Replace and program the Body Control Module per Service Information.
    2. Perform BODY VERIFICATION TEST .
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