Diagnostic Test

1) FUEL LEVEL SENSOR VOLTS ABOVE 4.9 VOLTS
NOTE: Diagnose any CAN - B and CAN - C Communication DTCs before continuing.

Ignition on, engine not running.

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

Is the Fuel Level Sensor voltage above 4.9 volts?

Yes
1. Go To 2).
No
1. Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
2. Perform BODY VERIFICATION TEST-VER 1. (Refer to STANDARD PROCEDURE - BODY VERIFICATION TEST - VER 1) .
2) FUEL LEVEL SENSOR
Turn the ignition off.

Disconnect the Fuel Pump Module electrical harness connector.

Ignition on, engine not running.

Connect a jumper wire between the (N4) Fuel Level Signal circuit and the (Z904) Fuel Level Sensor Ground circuit in the Fuel Pump Module harness connector.

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

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

Yes
1. Replace the Fuel Level Sensor.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Go To 3).
  NOTE: Remove the jumper wire before continuing.
3) (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE

Fig 1: MEASURING FOR VOLTAGE ON THE FUEL LEVEL SIGNAL CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Disconnect the C2 Cluster harness connector.

Ignition on, engine not running.

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

Is the voltage above 5.2 volts?

Yes
1. Repair the short to battery voltage in the (N4) Fuel Level Signal circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Go To 4).
4) (N4) FUEL LEVEL SIGNAL CIRCUIT OPEN

Fig 2: MEASURING RESISTANCE OF THE FUEL LEVEL SIGNAL CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Measure the resistance of the (N4) Fuel Level Signal circuit from the Fuel Pump Module harness connector to the C2 Cluster harness connector.

Is the resistance below 5.0 ohms?

Yes
1. Go To 5).
No
1. Repair the open in the (N4) Fuel Level Signal circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
5) (Z904) FUEL LEVEL SENSOR GROUND CIRCUIT OPEN

Fig 3: MEASURING RESISTANCE OF THE FUEL LEVEL SENSOR GROUND CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Measure the resistance of the (Z904) Fuel Level Sensor Ground circuit from the Fuel Pump Module harness connector to the C2 Cluster harness connector.

Is the resistance below 5.0 ohms?

Yes
1. Go To 6).
No
1. Repair the open in the (Z904) Fuel Level Sensor Ground circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
6) INSTRUMENT CLUSTER
NOTE: Before continuing, check the Instrument Cluster 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 the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Replace and program the Instrument Cluster per Service Information.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .