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P0118 Engine Coolant Temperature Sensor Circuit High
What it means
The coolant temperature sensor signal is reading abnormally high voltage (usually meaning very cold or an open circuit).
Severity: Moderate
Can I drive it? Drivable with care; can cause hard starting, poor mileage, or fans running constantly. Watch your temperature gauge.
Common causes (most likely first)
- Faulty coolant temperature sensor
- Unplugged or damaged connector
- Open wiring
Likely fixes
- Inspect connector and wiring
- Replace coolant temp sensor
DIY parts cost
$15–$60
Approximate estimate
Shop repair cost
$100–$250
Approximate estimate, parts + labor
DIY difficulty
Easy
Varies by vehicle
Cost ranges are rough, approximate U.S. estimates and vary widely by vehicle, region, and parts brand. Always confirm the diagnosis before buying parts.
Parts you may need
- Coolant temperature sensorCheck price
- CoolantCheck price
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