P0217
Engine Coolant Over Temperature Condition
- Severity
- Critical
- Driving
- Stop driving
The engine is overheating. This is one of the few fault codes that describes damage happening right now rather than a component that has failed. An overheating engine warps cylinder heads, destroys head gaskets and can seize outright, and the difference between an inconvenience and a new engine is often a matter of minutes.
Possible causes
- CommonLow coolant level, usually from a leak
- CommonFailed thermostat stuck closed
- CommonCooling fan not running - failed fan, relay, fuse or temperature switch
- CommonFailed water pump, or a broken belt driving it
- CommonAir lock in the cooling system after a previous repair
- PossibleBlocked radiator, externally with debris or internally with deposits
- PossibleHead gasket failure pressurising the cooling system
What you might notice
- Temperature gauge in the red
- Steam from the bonnet
- Coolant warning light
- Sweet smell of coolant
- Loss of power
- Engine cutting out or refusing to restart
What to check, in order
- Stop as soon as it is safe and switch the engine off. Every further minute of running makes the damage worse and more expensive.
- Do not open the expansion tank or radiator cap while the engine is hot. The system is pressurised and the coolant is above its normal boiling point - opening it sprays boiling coolant out and causes serious scalds. Wait until it is cold.
- Once cool, check the coolant level and look underneath for leaks and for a broken belt.
- Check whether the cooling fan runs when the engine is hot. A dead fan produces overheating in traffic while the car stays cool on the motorway - a very recognisable pattern.
- Check the top and bottom radiator hoses once warm. A cold bottom hose on a hot engine points at a thermostat stuck closed.
- Do not drive it to a garage on the assumption that it will be fine for a few miles. Have it recovered.
Read this code from your own car
Plug an ELM327 adapter into the OBD-II port under the dashboard. Pin16 reads every stored, pending and permanent code, explains each one like this page does — offline, with no account — and shows what the car recorded when the fault was set.
Where this code sits
P00xxP01xxP02xxP03xxP04xxP05xxP06xxP07xxP08xxP09xxP0AxxP0BxxP0CxxP0DxxP0ExxP0FxxP10xxP11xxP12xxP13xxP14xxP15xxP16xxP17xxP18xxP19xxP1AxxP1BxxP1CxxP1DxxP1ExxP1FxxP20xxP21xxP22xxP23xxP24xxP25xxP26xxP27xxP28xxP29xxP2AxxP2BxxP2CxxP2DxxP2ExxP2FxxP30xxP31xxP32xxP33xxP34xxP35xxP36xxP37xxP38xxP39xxP3AxxP3BxxP3CxxP3DxxP3ExxP3Fxx
Fuel and air metering - injector circuits
P0200P0201P0202P0203P0204P0205P0206P0207P0208P0209P0210P0211P0212P0213P0214P0215P0216P0217P0218P0219P0220P0221P0222P0223P0224P0225P0226P0227P0228P0229P0230P0231P0232P0233P0234P0235P0236P0237P0238P0239P0240P0241P0242P0243P0244P0245P0246P0247P0248P0249P0250P0251P0252P0253P0254P0255P0256P0257P0258P0259P0260P0261P0262P0263P0264P0265P0266P0267P0268P0269P0270P0271P0272P0273P0274P0275P0276P0277P0278P0279P0280P0281P0282P0283P0284P0285P0286P0287P0288P0289P0290P0291P0292P0293P0294P0295P0296P0297P0298P0299