DTC P0125 - Insufficient Coolant Temp. For Closed Loop Fuel Control
- Check for proper thermostat operation. Ensure coolant does not flow through radiator when engine is cold (stuck-open thermostat). Repair as necessary. If thermostat is okay, go to next step.
- Remove Engine Coolant Temperature (ECT) sensor located near coolant outlet. Using an ohmmeter, measure resistance of ECT sensor while immersed in container of water. Heat or cool water and compare with values of ECT SENSOR RESISTANCE table. Replace ECT sensor if resistance is not as specified. If ECT sensor is okay, go to next step.
ECT SENSOR RESISTANCE
| Temperature °F (°C) |
Ohms |
| 32 (0) |
5740 |
| 68 (20) |
2280-2610 |
| 104 (40) |
1150 |
| 140 (60) |
584 |
| 176 (80) |
303-326 |
- Check for high resistance in Light Green/Black wire or Gray/White wire between ECT sensor and PCM. Repair as necessary. If wires are okay, replace PCM. Retest system.