Error: Engine Over Temperature
The engine coolant temperature is too high.
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 computer is seeing that the coolant temperature is above the normal range, typically over 230°F (110°C), indicating potential overheating.
What the computer is actually seeing
The Engine Control Module (ECM) is reading the engine coolant temperature sensor voltage which varies between 0.5 volts (cold) and 4.5 volts (hot). If the voltage indicates temperatures above 230°F (110°C) for an extended period, it triggers the fault.
What a healthy reading looks like
Normal coolant temperatures should be between 180°F and 210°F (82°C to 99°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 coolant level in the reservoir and radiator. Refill if low.
- 22. Inspect for external leaks around hoses, radiator, and water pump.
- 33. Test the coolant temperature sensor using a multimeter for proper voltage output.
- 44. Check for proper operation of the thermostat by verifying if the engine reaches operating temperature and the radiator gets hot after a certain time.
- 55. Ensure the water pump is circulating coolant properly under engine operation.
Common causes
- Low coolant level
- Faulty coolant temperature sensor
- Cooling system leaks
- Faulty thermostat
- Worn out water pump
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive my vehicle with this code?
No, driving with an overheating engine can lead to severe engine damage.
Will this code come back after I clear it?
If the underlying issue isn't fixed, the code will likely return after the next drive cycle.
Why does this code sometimes appear with SPN 1006?
SPN 1006 relates to engine coolant temperature too, indicating that both are pointing to an overheating issue.
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