Engine Coolant Temperature Above Normal Operating Range
The engine coolant temperature exceeded the normal range.
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 is getting too hot, which can cause serious damage if not fixed.
What the computer is actually seeing
The engine control module (ECM) is receiving a coolant temperature reading above 220°F (104°C) for more than 2 seconds.
What a healthy reading looks like
Normal operating range is between 190°F and 220°F (88°C to 104°C).
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 engine coolant level. Is it below the minimum? Yes - top up the coolant and monitor for leaks. No - proceed to the next step.
- 22. Inspect the coolant for contamination or blockages. Is the coolant clear and flowing freely? Yes - proceed to the next step. No - flush the system and replace with fresh coolant.
- 33. Measure the temperature at the thermostat housing. Is the temperature above normal operating range when the engine is at operating temperature? Yes - replace the thermostat. No - proceed to the next step.
- 44. Test the coolant temperature sensor with a multimeter. Is the signal voltage between 0.5V and 4.5V when the engine is at normal operating temperature? Yes - check wiring and connectors for damage. No - replace the coolant temperature sensor.
Common causes
- Low coolant level
- Failed thermostat stuck closed
- Coolant leaks or blockages
- Faulty coolant temperature sensor
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
No, driving can cause engine damage due to overheating.
Will this code come back after I fix it?
If the underlying issue is resolved, the code should clear its self after a few drive cycles.
Why does this code pair with other codes?
These codes often indicate related issues, like cooling system failures or sensor malfunctions affecting temperature readings.
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