GPEC

P0461-FUEL LEVEL SENSOR 1 PERFORMANCE





For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
With engine run time greater than 128 seconds.

- Set Condition:
The PCM detects no change in Fuel Level Sensor 1 circuit voltage over time during monitoring.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Initial Inspection and Diagnostic Overview

Diagnostic Test

1. DTC IS ACTIVE
Turn the ignition on.
With the scan tool, select View DTCs and review the DTC environmental information.
Is the good trip counter greater than 0?

Yes

- The DTC is not active at this time. Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Checking For An Intermittent DTC

No

- Go to 2

2. EXTERIOR FUEL TANK DAMAGE
Inspect the exterior of the fuel tank for any damage that may restrict the movement of the fuel level sensor floats.
Were any problems found?

Yes

- Replace the fuel tank as necessary.
- Perform the Body Verification Test Ver. 1. Body Verification Test

No

- Go to 3

3. FUEL PUMP MODULE WIRING AND CONNECTORS
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Fuel Pump Module harness connector and the Instrument Cluster (CCN).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes

- Repair as necessary.
- Perform the Body Verification Test Ver. 1. Body Verification Test

No

- Go to 4

4. FUEL LEVEL SIGNAL 1 CIRCUIT VOLTAGE




Turn the ignition off.
Disconnect the Fuel Pump Module harness connector.
Turn the ignition on.
With the scan tool, read the Fuel Level Sensor 1 circuit voltage.

NOTE: The sensor voltage should be approximately 5.0 volts (plus or minus.1 volt) with connector disconnected.

Turn the ignition off.
Connect a jumper wire between ground and the (N4) Fuel Level Signal 1 circuit in the Fuel Pump Module harness connector.
Turn the ignition on.
With the scan tool, read the Fuel Level Sensor 1 circuit voltage.

NOTE: The sensor voltage should be approximately 0.0 volts (plus or minus.1 volt) with the jumper wire in place.

Does the scan tool display the voltage as described above?

Yes

- Go to 5

No

- Go to 8

5. (Z916) GROUND CIRCUIT OPEN OR HIGH RESISTANCE




Turn the ignition off.
Measure the resistance between ground and the (Z916) Ground circuit in the Fuel Pump Module harness connector.
Is the resistance below 5.0 ohms?

Yes

- Go to 6

No

- Repair the (Z916) Ground for an open circuit or high resistance.
- Perform the Body Verification Test Ver. 1. Body Verification Test

6. FUEL TANK WIRING HARNESS INSPECTION

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.
Inspect the wiring and connectors between the Fuel Pump Module harness connector and both Fuel Level Sensors.
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Were any problems found?

Yes

- Repair as necessary.
- Perform the Body Verification Test Ver. 1. Body Verification Test

No

- Go to 7

7. FUEL LEVEL SENSOR 1
Remove Fuel Level Sensor 1.
Inspect Fuel Level Sensor 1 and the inside of the fuel tank for any condition that would restrict the movement of the fuel level sensor float.
Were any problems found?

Yes

- Repair or replace the fuel tank components as necessary.
- Perform the Body Verification Test Ver. 1. Body Verification Test

No

- Replace the Fuel Level Sensor 1.
- Perform the Body Verification Test Ver. 1. Body Verification Test

8. (N4) FUEL LEVEL SIGNAL 1 CIRCUIT SHORTED TO VOLTAGE




Turn the ignition off.
Disconnect the Instrument Cluster (CCN) connector.
Turn the ignition on.
Measure the voltage of the (N4) Fuel Level Signal 1 circuit in the Fuel Level Sensor 1 harness connector.
Is there any voltage present?

Yes

- Repair the (N4) Fuel Level Signal 1 circuit for a short to voltage.
- Perform the Body Verification Test Ver. 1. Body Verification Test

No

- Go to 9

9. (N4) FUEL LEVEL SIGNAL 1 CIRCUIT SHORTED TO GROUND




Turn the ignition off.
Measure the resistance between ground and the (N4) Fuel Level Signal 1 circuit in the Fuel Level Sensor 1 harness connector.
Is the resistance above 100 ohms?

Yes

- Go to 10

No

- Repair the (N4) Fuel Level Signal 1 circuit for a short to ground.
- Perform the Body Verification Test Ver. 1. Body Verification Test

10. (N4) FUEL LEVEL SIGNAL 1 CIRCUIT OPEN OR HIGH RESISTANCE




Measure the resistance of the (N4) Fuel Level Signal 1 circuit between the Fuel Level Sensor 1 harness connector and the Instrument Cluster (CCN) harness connector.
Is the resistance below 5.0 ohms?

Yes

- Go to 11

No

- Repair the (N4) Fuel Level Signal 1 circuit for an open circuit or high resistance.
- Perform the Body Verification Test Ver. 1. Body Verification Test

11. INSTRUMENT CLUSTER (CCN)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Fuel Pump Module and the Instrument Cluster (CCN).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes

- Repair as necessary.
- Perform the Body Verification Test Ver. 1. Body Verification Test

No

- Replace the Instrument Cluster (CCN).
- Perform the Body Verification Test Ver. 1. Body Verification Test