Engine Over Temperature
The engine is running hotter than normal.
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)
Your engine's temperature is above the safe limit, usually over 220°F (104°C), risking overheating and potential damage.
What the computer is actually seeing
The engine control module (ECM) monitors the engine coolant temperature sensor (ECT) signal. When it reads a temperature exceeding 220°F (104°C), it triggers this code.
What a healthy reading looks like
Engine coolant should stay between 190°F (88°C) and 220°F (104°C) under normal operating conditions.
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 coolant level**: Ensure the coolant is at the proper level in the reservoir. If it's low, top it up and check for leaks.
- 22. **Inspect ECT sensor**: Measure the resistance of the ECT sensor to see if it matches specs. For most sensors, expect about 0.5 to 5 volts at operating temp.
- 33. **Thermostat operation**: With the engine warmed up, feel the upper and lower radiator hoses. If the upper is hot, but the lower is cool, the thermostat may be stuck closed.
- 44. **Inspect cooling fans**: Verify the cooling fans engage when the temperature exceeds 220°F (104°C). If not, check fuse and relay operation.
- 55. **Check for blockages**: Inspect radiator for debris or internal blockages that could prevent proper cooling. Clear any obstructions.
Common causes
- Low coolant level or leakage
- Faulty ECT sensor
- Cooling system blockage
- Failed thermostat
- Inoperative fans
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
No, it's not safe to drive if the engine is overheating, as it can cause serious engine damage.
Will this issue come back after fixing?
If the root cause is properly fixed, this code should not return.
Why does this code pair with other codes?
Often, overheating can be related to other cooling system failures, leading to multiple codes being set simultaneously.
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