Is it safe to drive with a P0118 code?

Severity is medium. Address P0118 sooner rather than later — driving with an active check engine light can worsen the problem or void emissions warranties.

How much does it cost to fix P0118?

Repair costs for P0118 typically range from $15 to $150 in the US, depending on the underlying cause. The most common fix is: Disconnected ECT connector.

What are the symptoms of P0118?

Check engine light. Cold-start hard / no-start. Cooling fans running at low temp. Erratic gauge.

Check Engine Code

P0118

Engine Coolant Temperature Sensor Circuit High Input

Severity: medium DIY difficulty: 1/5 Typical cost: $15–$150

Last updated April 30, 2026

What P0118 means

Counterpart to P0117. ECM is seeing an open circuit or implausibly hot coolant reading from the ECT sensor.

Symptoms

Check engine light
Cold-start hard / no-start
Cooling fans running at low temp
Erratic gauge

Likely causes (most common first)

Disconnected ECT connector
Open ECT sensor
Broken signal wire
Corroded pins

Can I keep driving?

Medium — drivable but fix soon

Typical repair cost

DIY fixes can start near $15 (parts only). Shop repairs for P0118 typically run up to $150 depending on the underlying cause and vehicle. Start with the most common cause — Disconnected ECT connector — before throwing parts at it.

Symptoms that match P0118

If you got here from a search query, one of these might describe what your car is actually doing:

Recommended parts & tools for P0118

Compare the parts and tools that pair with AXLY:

Best Engine Coolant & Antifreeze for Cars (2025) → Browse all car gear →

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Related codes

P0117 P0125 P0128

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