P0117
Thread Starter
Joined: May 2006
Posts: 29,661
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From: Sheboygan Wisconsin






P0117
Description
ECT SENSOR CIRCUIT LOW VOLTAGE
Engine Coolant Temperature (ECT) sensor is a thermistor that
varies resistance based on temperature. As temperature of sensor
increases, resistance decreases. Low temperature will result in a high
signal voltage. DTC will set when PCM sees an excessively high ECT
sensor voltage signal.
Potential Symptoms
Description
ECT SENSOR CIRCUIT LOW VOLTAGE
Engine Coolant Temperature (ECT) sensor is a thermistor that
varies resistance based on temperature. As temperature of sensor
increases, resistance decreases. Low temperature will result in a high
signal voltage. DTC will set when PCM sees an excessively high ECT
sensor voltage signal.
Potential Symptoms
- Very poor fuel economy
- Engine wont start
- Engine may start, but run very poorly, blowing black smoke, running very rough and misfiring
- SES light
- Corroded connection at the sensor
- Brake in the ground wire between sensor and PCM
- A short in the wire between the sensor and the PCM
- Defective ECT sensor
- Check connection at the sensor, clean if needed
- Test ground wire
- Test signal wire for short.
- Replace ECT sensor.






