Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the primary fuel level sensor.
- Ignition OFF, test for less than 1 ohm between the low reference circuit terminal 4 and ground.
- If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuits tests normal, replace the ECM.
- Install a signal generator and instrument panel tester between the fuel level sensor signal circuit terminal 1 and the low reference circuit terminal 4.
- Ignition ON, vary the signal generator resistance between 40 and 250 ohms. Verify that the scan tool Fuel Tank Level Remaining parameter displays a range that varies between 5 and 95 percent as the signal generator resistance changes.
- If not displaying the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the ECM
- If all circuits test normal, perform the fuel level sensor component test before replacing the primary fuel level sensor.