P0116

Wiring Diagram:

P0116- ECT SENSOR PERFORMANCE
The engine coolant temperature (ECT) sensor is a thermistor that varies resistance according to changes in engine coolant temperature. The ECM supplies a five volt reference though a pull-up resistor to the sensor, which is connected to ground. When the sensor is cold it has high resistance (high signal voltage at ECM). As the sensor temperature increases, its resistance decreases (lower signal voltage at ECM). The ECM uses the signal voltage to determine engine coolant temperature. The ECM calculates a modeled temperature using start up ECT. MAF, MAP and engine run time, then compares this value to the ECT sensor signal. DTC P0116 sets when the ECT sensor signal deviates more than 12°C or 22°F from the ECM modeled temperature.

DTC PARAMETERS
DTC P0116 sets when the ECT sensor signal deviates more than 12°C or 22°F from the ECM modeled temperature when engine speed is greater than 20 rpm.

DTC P0116 runs continuously with engine cranking/running.

P0116 is a type B DTC

DIAGNOSTIC AIDS
DTC P0116 indicates that the ECT sensor readings are valid, but deviate more than 12°C or 22CF from the ECM modeled temperature.

Possible causes of out of range engine cool ant temperature:
^ Skewed ECT sensor
Very low ambient temperatures
^ Corrosion in connector or resistance in wiring
^ Poor or corroded connections in ECT circuit
^ Thermostat malfunction
^ Cooling fan(s) malfunction

ECT sensor reading may be compared to IAT sensor reading on Scan tool after the vehicle has been sitting longer than 6 hours with the ignition Off. Both readings should be within 6°C or 10°F of each other

Refer to ECT General Description for a Temperature vs. Resistance chart.