Operation CHARM: Car repair manuals for everyone.

P0118

DTC P0118: ECT Sensor Circuit High Voltage

1. Turn the ignition switch ON (II).
2. Check the ECT with the scan tool or the HDS.

Is -4 °F (-20 °C) or less, or 5 V indicated?

YES - Go to step 3.

NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the ECT sensor and at the ECM/PCM.

3. Turn the ignition switch OFF.
4. Disconnect the ECT sensor 2P connector.




5. Connect the ECT sensor 2P connector terminals No.1 and No.2 with a jumper wire.
6. Turn the ignition switch ON (II).
7. Check the ECT with the scan tool or the HDS.

Is -4 °F (-20 °C) or less, or 5 V indicated?

YES - Go to step 8.

NO - Replace the ECT sensor.

8. Turn the ignition switch OFF.
9. Remove the jumper wire.




10. Connect ECM/PCM connector terminals A10 and B8 with a jumper wire.
11. Turn the ignition switch ON (II).
12. Check the ECT with the scan tool or the HDS.

Is -4 °F (-20 °C) or less, or 5 V indicated?

YES - Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM.

NO - Repair open in the wire between the ECM/PCM (A10, B8) and the ECT sensor.