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P2181

P2181

Diagnosis information - DME

Thermostat stuck open

Diagnostic conditions
- Vehicle speed > 15 km/h (9 mph)
- Engine speed 1,000 ... 5,000 rpm
- Air mass throughput under the aforementioned conditions: 3.0 kg
- Coolant temperature when engine starts < 60 °C (140 °F)
- Ambient temperature -6.8 °C (19.8 °F) ... 60 °C (140 °F)

NOTE: In this context, please also observe the function description.

Possible fault causes
- Thermostat faulty (stuck open)
- Coolant temperature sensor faulty
- Tiptronic vehicles only: coolant shutoff valve open (mechanical fault, lack of vacuum...)