Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the ambient air temperature sensor.
- Ignition OFF, test for less than 1.0 ohm of resistance between the low reference circuit and ground.
- If greater than 1.0 ohm, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the engine control module (ECM)/powertrain control module (PCM).
- Ignition ON, install a 3-amp fused jumper between the ambient air temperature sensor signal circuit and the low reference circuit. Verify SC is displayed on the DIC display.
- If SC is not displayed, test the ambient air temperature sensor signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the instrument panel cluster (IPC).
- If all circuits test normal, test or replace the ambient air temperature sensor.