P0118high severityPowertrain
ECT Sensor 1 Circuit High Input
on 2004-2006 Audi A8 4.2L V8 · AWD
What this code 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
Repair notes
Repair open circuit or replace sensor. CAUTION: Engine may overheat if fans do not activate.
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