DTC P0460: Fuel Level Unit No Change Over Miles: Testing
NOTE:
If DTC P0462 or P0463 is also present, diagnose those DTCs first.
- Turn ignition on. Using scan tool, read DTCs. If GOOD TRIP counter is displayed and equal to zero, go to next step. If GOOD TRIP counter is not displayed and equal to zero, go to step 8 .
- Visually inspect fuel tank for damage that may restrict fuel level sensor float from moving. If fuel tank is okay, go to next step. If fuel tank is not okay, replace fuel tank.
- Turn ignition off. Disconnect fuel pump module harness connector. See Figure . Disconnect Body Control Module (BCM) harness connector located on back side of junction block. Junction block is located on left end of instrument panel. Measure resistance between ground and signal circuit (Dark Blue wire) at fuel pump module harness connector. If resistance is 100 ohms or more, go to next step. If resistance is less than 100 ohms, repair short to ground in Dark Blue wire.
- Measure resistance of signal circuit (Dark Blue wire) between fuel pump module harness connector and terminal No. 7 at BCM C4 harness connector. See Fig 1 . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Dark Blue wire.
- Measure resistance between ground and Black wire at fuel pump module harness connector terminal No. 2. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in ground circuit.WARNING: Fuel system is under constant pressure even when ignition is off. Open fuel system with caution.
- Release fuel pressure. See FUEL SYSTEM PRESSURE RELEASE . Remove fuel tank. Remove fuel pump module. Visually inspect inside of fuel tank for obstructions or deformities. Also, inspect fuel level sensor float arm for damage. If any problems are found, repair as necessary. If no problems are found, go to next step.
- If no other possible causes are remaining, replace fuel level sensor.
- Conditions that set DTC are not present at this time. Perform the following to help identify intermittent condition:
- With engine running at normal operating temperature, wiggle related wiring harness while monitoring related parameters on scan tool. If voltage changes or DTC sets while wiggling wiring harness, repair connectors or wiring harness where wiggling caused voltage to change or DTC to set.
- Review freeze frame information on scan tool. Duplicate conditions present when DTC was set.
- Refer to any technical service bulletins that may apply.
- Visually inspect related wiring harness. Check for chafed, pierced, pinched or partially broken wires.
- Visually inspect related wiring harness connectors. Check for broken, bent, pushed out or corroded terminals.
If a problem is found, repair as necessary. If no problems are found, test is complete.