Engine Coolant Temperature High
The engine coolant temperature sensor is reporting a high temperature.
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 thinks the coolant is running hotter than it should, which could be a sign of overheating or a sensor issue.
What the computer is actually seeing
The engine control module (ECM) receives a voltage from the coolant temperature sensor that exceeds the expected range, typically above 240°F (115°C).
What a healthy reading looks like
Normal coolant temperature should range from 180°F to 220°F (82°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.
- 1Check coolant level; ensure it meets the required level. If low, refill and recheck for codes.
- 2Inspect the coolant temperature sensor wiring for shorts or disconnection; repair as necessary.
- 3Test the coolant temperature sensor with a multimeter to verify resistance values. Compare to expected values in the vehicle's service manual.
- 4Check for signs of engine overheating (e.g., coolant leaks or thermal anomalies around the engine).
- 5If coolant level is good, wiring is intact, and sensor tests fine, inspect the thermostat for proper operation.
Common causes
- Failed coolant temperature sensor
- Coolant level low or air in the system
- Engine overheating due to a stuck thermostat or failed water pump
- Shorted wiring or corroded connectors
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's best to fix this code soon; operating an engine at high coolant temperatures can cause damage.
Will this code come back after I clear it?
If the underlying issue is not fixed, yes, it will return.
Why does this code appear with other codes?
High engine temperatures can affect multiple systems, leading to multiple codes being generated.
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