17 Closed Loop Temperature Not Reached - (P 0125)

17 CLOSED LOOP TEMPERATURE NOT REACHED - (P 0125)

The Powertrain Control Module (PCM) sends a 5-volt analog signal to the Engine Coolant Temperature (ECT) sensor. The ECT is a thermistor, the resistance of which increases as temperature decreases (NTC-Negative Thermal Co-efficient). The PCM uses this sensors information to calculate pulse width. It is also used to determine O2 feedback closed loop timers. If the sensor malfunctions, closed loop may be delayed or possibly never achieved, causing an increase of exhaust emissions.

ENABLING CONDITIONS
This DTC will be stored if engine temperature remains below 60° F. for ten minutes of operation and no engine coolant temperature sensor code has been set.

See code 22 for more information.

This malfunction could possibly be caused by problems with any of the following components:

- ECT sensor
- Wiring or related connectors of the ECT sensor (corrosion)
- PCM