Engine Cooling System Performance
Indicates a problem with the engine's cooling system performance.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The engine's computer sees that the coolant isn't staying at the normal temperature range, which could mean it's overheating or not cooling properly.
What the computer is actually seeing
The engine control unit monitors the coolant temperature, which should typically stay between 185°F and 220°F during operation. If it sees temperatures consistently outside this range, it triggers the fault code.
What a healthy reading looks like
Coolant temperature should be between 185°F and 220°F. If the temperature exceeds 250°F, it indicates a potential overheating condition.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the coolant level. Is it below the minimum? If yes, add coolant and retest.
- 22. Inspect for leaks in the cooling system. Are there any visible signs of leaks? If yes, repair the leaks and retest.
- 33. Check the condition of the thermostat. Is it stuck closed? Replace if necessary, then retest.
- 44. Test the coolant temperature sensor. Use a multimeter to check for proper resistance. Should be around 0.5-2.5k ohms at room temp; replace if readings are off.
- 55. Check the radiator for blockages or debris. Is airflow restricted? Clean or repair as needed.
Common causes
- Low coolant level
- Faulty thermostat
- Coolant leaks
- Blocked radiator
- Faulty coolant temperature sensor
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's not advisable to drive for long with this code. If the engine overheats, it can cause serious damage.
Will this code come back after clearing it?
If the underlying issue isn’t fixed, it will likely return soon after clearing.
Why does this code pair with others?
Cooling system issues can often impact multiple sensors and systems, leading to more than one code being triggered.
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