P0118
DTC P0118: ECT Sensor Circuit High Voltage1. Turn the ignition switch ON (II).
2. Check the ECT SENSOR in the DATA LIST with 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 the ECM.
3. Turn the ignition switch OFF.
4. Disconnect the ECT sensor 2P connector.
5. Connect 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 SENSOR in the DATA LIST with 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. Turn the ignition switch ON (II).
11. Measure voltage between ECT sensor 2P connector terminal No.1 and body ground.
Is there about 5 V?
YES - Go to step 12.
NO - Go to step 14.
12. Connect ECT sensor 2P connector terminal No.2 to body ground with a jumper wire.
13. Check for continuity between ECM connector terminal C18 and body ground.
Is there continuity?
YES - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.
NO - Repair open in the wire between the ECM (C18) and the ECT sensor.
14. Measure voltage between ECM connector terminal C26 and body ground.
Is there about 5 V?
YES - Repair open in the wire between the ECM (C26) and the ECT sensor.
NO - Update the ECM if it does not have the latest software, or substitute a known-good ECM , then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.