P0116 - Engine Coolant Temperature Circuit Range/Performance
The coolant temperature sensor signal is outside the expected operating range.
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Code Overview
The coolant temperature sensor signal is outside the expected operating range.
Common Causes
- Coolant temperature sensor reading skewed
- Thermostat stuck open or not regulating correctly
- Low coolant level or trapped air in the system
- Wiring or connector issue at the ECT sensor
Symptoms
- Temperature reading does not match actual warm-up behavior
- Poor fuel economy during warm-up
- Cooling fan or temperature-gauge behavior may seem off
Diagnostic Steps
- Compare ECT to ambient temperature on a cold start
- Inspect coolant level and make sure the system is full with no trapped air
- Review warm-up behavior to see whether the thermostat is regulating correctly
- Inspect the ECT connector and wiring before replacing parts
Repair Difficulty
Moderate
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