Common Symptoms
- Check Engine Light illuminated
- Engine takes longer than normal to reach operating temperature
- Cooling fans run continuously or not at all
- Poor fuel economy
- Rough idle or hesitation when cold
- Temperature gauge reads erratically or stays cold
Most Likely Root Causes
- Faulty engine coolant temperature sensor
- Thermostat stuck open or closed
- Low coolant level or air in cooling system
- Corroded or damaged wiring harness to ECT sensor
- Faulty engine control module
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Component Location
The engine coolant temperature sensor is typically located near the thermostat housing or on the engine block coolant passage.
Manufacturer Notes
This code indicates the ECM detected an implausible coolant temperature reading compared to engine runtime and intake air temperature.
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