P0463-FUEL LEVEL SENSOR 1 CIRCUIT HIGH

For a complete wiring diagram Refer to Section 8W.

When Monitored:
Ignition on and battery voltage above 10.4 volts.
Set Condition:
The fuel level sensor signal voltage at the PCM goes above 4.9 volts for more than 90 seconds. One Trip Fault. Three good trips to turn off the MIL.

(N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

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

Go To 2

Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

2. FUEL LEVEL SENSOR

Turn the ignition off.
Disconnect the Fuel Pump Module electrical harness connector.
Ignition on, engine not running.
With a scan tool, monitor the Fuel Level Signal voltage.
Connect a jumper wire between the (N4) Fuel Level Signal circuit and the (K900) Sensor ground circuit.

Did the Fuel Level voltage change from approximately 5 volts to 0 volts?

Yes

Replace the Fuel Level Sensor.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

Go To 3
NOTE: Remove the jumper wire before continuing.

3. (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE

Turn the ignition off.
Disconnect the C7 TIPM 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 0 volts?

Yes

Repair the short to battery voltage in the (N4) Fuel Level Signal circuit.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

Go To 4

4. (N4) FUEL LEVEL SIGNAL CIRCUIT OPEN

Turn the ignition off.
Measure the resistance of the (N4) Fuel Level Signal circuit from the Fuel Pump Module harness connector to the C7 TIPM harness connector.

Is the resistance below 5.0 ohms?

Yes

Go To 5

Repair the open in the (N4) Fuel Level Signal circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

5. (K900) SENSOR GROUND CIRCUIT OPEN

Disconnect the C2 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 (K900) Sensor Ground circuit from the Fuel Pump Module harness connector to the TIPM harness connector.

Is the resistance below 5.0 ohms?

Yes

Go To 6

Repair the open in the (K900) Sensor Ground circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

6. TOTALLY INTEGRATED POWER MODULE

NOTE: Before continuing, check the TIPM 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 any problems found?

Yes

Repair as necessary.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

Replace the Totally Integrated Power Module per Service Information.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)