Diagnostic Test

1) ACTIVE DTC

Fig 1: SCAN TOOL (STARSCAN)
Courtesy of DAIMLERCHRYSLER CORP.

NOTE: Diagnose any CAN - C or CAN - B Communication DTCs before continuing.

NOTE: Diagnose P0462 or P0463 first, if set along with P0461.

Ignition on, engine not running.

With a scan tool, read DTCs.

Is the DTC active at this time?

Yes
1. Go To step 2).
No
1. Refer to INTERMITTENT CONDITION .
2. Perform NGC POWERTRAIN VERIFICATION TEST VER - 5 .
2) VISUALLY INSPECT FUEL TANK
Visually inspect the Fuel Tank for damage that may restrict the Fuel Sending Unit float from moving.

Is the Fuel Tank OK?

Yes
1. Go To step 3).
No
1. Replace the Fuel Tank as necessary.
2. Perform NGC POWERTRAIN VERIFICATION TEST VER - 5 .
3) (N4) FUEL LEVEL SIGNAL CIRCUIT OPEN

Fig 2: Checking Fuel Level Sensor Signal Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Disconnect the Fuel Pump Module harness connector.

Disconnect the C2 Cluster harness connectors.

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 step 4).
No
1. Repair the open in the (N4) Fuel Level Signal circuit.
2. Perform BODY VERIFICATION TEST - VER 1 .
4) (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO GROUND

Fig 3: Checking Fuel Level Sensor Signal Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Measure the resistance between ground and the (N4) Fuel Level Signal circuit in the Fuel Pump Module 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 - VER 1 .
No
1. Go To step 5).
5) (Z210) FUEL LEVEL SENSOR GROUND CIRCUIT OPEN

Fig 4: Checking Fuel Level Sensor Ground Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Measure the resistance of the (Z210) 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 step 6).
No
1. Repair the open in the (Z210) Fuel Level Sensor Ground circuit.
2. Perform BODY VERIFICATION TEST - VER 1 .
6) INTERNAL INSPECTION OF THE FUEL TANK
WARNING: The fuel system is under a constant pressure (even with the engine off). Before testing or servicing any fuel system hose, fitting or line, the fuel system pressure must be released. Failure to follow these instructions can result in personal injury or death.

Remove the Fuel Tank. Refer to TANK-FUEL .

Remove the Fuel Pump Module.

Visually inspect the inside of the Fuel Tank for any obstructions or deformities.

Inspect the Fuel Pump Module Float arm for damage.

Were any problems found?

Yes
1. Repair or replace as necessary.
2. Perform NGC POWERTRAIN VERIFICATION TEST VER - 5 .
No
1. Go To step 7).
7) FUEL LEVEL SENSOR
If there are no possible causes remaining, view repair.

Repair
1. Replace the Fuel Level Sensor.
2. Perform BODY VERIFICATION TEST - VER 1 .