P0118
PowertrainTemperature Sensorhigh severityECT Sensor 1 Circuit High Input
What P0118 Means
The ECT sensor voltage is higher than expected, indicating very low temperature or open circuit.
Symptoms
- Check Engine Light
- Rich running at operating temp
- Poor fuel economy
- Fans not coming on
Common Causes
- Open circuit
- Disconnected sensor
- Faulty sensor
- Corroded connector
Diagnostic Steps
- Test sensor resistance
- Check for open circuits
- Inspect connector
Where to start: Repair open circuit or replace sensor. CAUTION: Engine may overheat if fans do not activate.
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