- Install scan tool. Start engine and check for DTCs. If DTC P0125 is present, go to next step. If DTC P0125 is not present, problem is intermittent. See INTERMITTENTS in «TESTS W/O CODES»(ref-16659) article.
- Check thermostat for proper operation. Replace as necessary. If thermostat is okay, go to next step.
- Using scan tool, check ECT sensor resistance. See ECT SENSOR RESISTANCE SPECIFICATIONS table. Replace as necessary. If ECT sensor resistance is okay, go to next step.
- Check circuit between ECT sensor and ECM connector terminals. Repair as necessary. See appropriate wiring diagram in «WIRING DIAGRAMS»(ref-16646) article. If circuit is okay, go to next step.
- Clear DTC. See CLEARING CODES under Self Diagnostic System section. Retest system. If DTC resets, replace ECM.
| Coolant Temperature °F (°C) | Ohms |
|---|---|
| 32 (0) | 5900 |
| 68 (20) | 2500 |
| 104 (40) | 1100 |
| 176 (80) | 300 |
ECT SENSOR RESISTANCE SPECIFICATIONS