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Diagnostic Test

  1. 1) FUEL LEVEL SENSOR VOLTS BELOW 0.0196 VOLT 

    Ignition on, engine not running.

    With the scan tool, read DTCs and record the related Freeze Frame data.

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

    Is the Fuel Level Sensor voltage below 0.0196 of a volt? 

    Yes 

    1. Go To step  2).

    No 

    1. Refer to INTERMITTENT CONDITION .
    2. Perform POWERTRAIN VERIFICATION TEST .
  2. 2) FUEL LEVEL SENSOR 
    Fig 1: Fuel Pump Module Harness Connector
    GC0046851Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the Fuel Pump Module harness connector.

    Ignition on, engine not running.

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

    Did the Fuel Level Sensor voltage change from below 0.4 of a volt to above 4.0 volts? 

    Yes 

    1. Replace the Fuel Level Sensor in accordance with the Service Information.
    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  7).

    Diesel 

    1. Go To step  10).
  4. 4) (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO GROUND 
    Fig 2: Measuring Resistance Between Ground And Fuel Level Signal Circuit
    GC0046852Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the C2 and C3 PCM harness connectors.

    Measure the resistance between ground and the (N4) Fuel Level Signal circuit at the Fuel Level Sensor harness connector.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the short to ground 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 SHORTED TO THE (K900) SENSOR GROUND 
    Fig 3: Measuring Resistance Between Fuel Level Signal Circuit And Sensor Ground Circuit
    GC0046853Courtesy of CHRYSLER LLC

    Measure the resistance between the (N4) Fuel Level Signal circuit and the (K900) Sensor ground circuit at the Fuel Pump Module harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Repair the short between the (K900) Sensor ground and the (N4) Fuel Level Signal circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To step  6).
  6. 6) 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 .
  7. 7) (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO GROUND 
    Fig 4: Measuring Resistance Between Ground And Fuel Level Signal Circuit
    GC0046854Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the BCM C2 harness connectors.

    Measure the resistance between ground and the (N4) Fuel Level Signal circuit at the Fuel Level Sensor harness connector.

    Is the resistance below 100 ohms? 

    Yes 

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

    No 

    1. Go To step  8).
  8. 8) (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO THE (K310) SENSOR GROUND 
    Fig 5: Measuring Resistance Between Fuel Level Signal Circuit And Sensor Ground Circuit
    GC0046855Courtesy of CHRYSLER LLC

    Measure the resistance between the (N4) Fuel Level Signal circuit and the (K310) Sensor ground circuit at the Fuel Pump Module harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Repair the short between the (K310) Sensor ground and the (N4) Fuel Level Signal circuit.
    2. Perform BODY VERIFICATION TEST .

    No 

    1. Go To step  9).
  9. 9) 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 .
  10. 10) (K304) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO GROUND 
    Fig 6: Measuring Resistance Between Ground And Fuel Level Signal Circuit
    GC0046856Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the BCM C2 harness connectors.

    Measure the resistance between ground and the (K304) Fuel Level Signal circuit at the Fuel Level Sensor harness connector.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the short to ground in the (K304) Fuel Level Signal circuit.
    2. Perform BODY VERIFICATION TEST .

    No 

    1. Go To step  11).
  11. 11) (K304) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO THE (K300) SENSOR GROUND 
    Fig 7: Measuring Resistance Between Fuel Level Signal Circuit And Sensor Ground Circuit
    GC0046857Courtesy of CHRYSLER LLC

    Measure the resistance between the (K304) Fuel Level Signal circuit and the (K300) Sensor ground circuit at the Fuel Pump Module harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Repair the short between the (K300) Sensor ground and the (N304) Fuel Level Signal circuit.
    2. Perform BODY VERIFICATION TEST .

    No 

    1. Go To step  12).
  12. 12) 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 BODY VERIFICATION TEST .
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