Circuit/System Testing
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- Ignition OFF, disconnect the harness connector at the fuel level sensor.
- Ignition OFF, test for less than 1 ohm between the low reference circuit terminal B and ground.
- If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
- Ignition ON, install a 3-amp fused jumper wire between the signal circuit terminal C and the low reference circuit terminal B. Verify the scan tool Fuel Tank Level Remaining parameter display is greater than 98 percent.
- If less than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
- If all circuits test normal, test or replace the fuel level sensor.