16501moderate severityPowertrain
Engine Coolant Temperature Circuit Low Input
on 2004 Volkswagen Beetle 1.8L Turbo I4 · FWD
What this code means
The coolant temperature sensor signal is too low (OBD P0117), indicating an implausibly high temperature reading. Usually a short or sensor fault.
Symptoms
- Cooling fan runs constantly
- Check engine light on
- Poor fuel economy
Common causes
- Short to ground in wiring
- Faulty coolant temperature sensor
- Connector corrosion
- Faulty ECM
Diagnostic steps
- Read live coolant temp data
- Inspect wiring for short to ground
- Test sensor resistance
- Check connector condition
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