Powertrain
generic / SAE
P050C
Cold Start Engine Coolant Temperature Performance
During cold-start the ECU expects coolant temperature to rise within a calibrated time window. Either the engine warms up too slowly (stuck-open thermostat, weak combustion) or the temperature signal does not reflect the actual warm-up.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number5 / 0C
Possible causes
- Thermostat stuck open - engine warms too slowly high
- Coolant temperature sensor drifts low medium
Symptoms
- Check engine light on
- Cooling fan runs constantly or not at all
- Cabin heater weak or excessively hot
- Possible long warm-up time or hard cold start
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 80–350 €
- Estimated time: 0.6–2 h
- Component: thermostat
- Component: coolant temperature sensor
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012