DTC P0125: ECT Sensor 1 Malfunction/Slow Response
- Start the engine, and let it idle for 5 minutes or more.
- Check ECT SENSOR 1 in the DATA LIST with the HDS.
Is about 10°F (-12 °C) or less indicated?
YES -Check for poor connections or loose terminals at ECT sensor 1, ECT sensor 2, and the PCM. If the connections and terminals are OK, replace ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ), then go to step 7.
NO -Go to step 3.
- Turn the ignition switch to LOCK (0).
- Allow the engine to cool to 104 °F (40 °C) or less.
- Start the engine, and let it idle until ECT SENSOR 1 reads about 158 °F (70 °C).
Does ECT SENSOR 2 also read about 158 °F (70 °C)?
YES -Go to step 6.
NO -Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at ECT sensor 1, ECT sensor 2, and the PCM.
- Check the thermostat (see
FAN MOTOR TEST
).
Is the thermostat OK?
YES -Check for poor connections or loose terminals at ECT sensor 1, ECT sensor 2, and the PCM. If the connections and terminals are OK, replace ECT sensor 1 (see ECT SENSOR 1 REPLACEMENT ), then go to step 7.
NO -Replace the thermostat (see THERMOSTAT REPLACEMENT ), then go to step 7.
- Turn the ignition switch to ON (II).
- Reset the PCM with the HDS.
- Turn the ignition switch to LOCK (0).
- Allow the engine to cool to 104 °F (40 °C) or less.
- Start the engine, and let it idle until ECT SENSOR 1 reads about 158 °F (70 °C).
Does ECT SENSOR 2 also show about 158 °F (70 °C)?
YES -Go to step 1 and recheck.
NO -Troubleshooting is complete.