Cooling System Performance
The engine cooling system does not reach or maintain the expected temperature within the diagnostic window — usually a stuck-open thermostat, but also a low coolant level or a stuck cooling fan that overcools the engine.
Affected components
- Thermostat
- Coolant temperature sensor
- Cooling fan
Common causes
- High likelihood: Thermostat stuck open
- Medium likelihood: Coolant level low
- Low likelihood: Cooling fan stuck on
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- A drive cycle may be required after repair
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.