Note. Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION ).
- Turn the ignition switch ON (II).
- Check the ECT SENSOR in the DATA LIST with the HDS. Is about 176°F (80°C) or higher, or 0.86 V or less indicated? YES- Go to step 3 . NO- Go to step 7 .
- Note the current coolant temperature.
- Turn the ignition switch OFF.
- Let the engine cool off for 1 hour.
- Check the ECT SENSOR in the DATA LIST with the HDS. Did the ECT change 3.6°F (2°C) or more? YES- Intermittent failure, system is OK at this time. Check the thermostat and the cooling system. NO- Go to step 10 .
- Note the current coolant temperature.
- Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, then let it idle.
- Check the ECT SENSOR in the DATA LIST with the HDS. Does the ECT change 3.6°F (2°C) or more? YES- Intermittent failure, system is OK at this time. Check the thermostat and the cooling system. NO- Go to step 10 .
- Turn the ignition switch OFF.
- Replace the ECT sensor (see «ECT SENSOR REPLACEMENT»(ref-220570-S34870321162006022000000) ).
- Turn the ignition switch ON (II).
- Reset the ECM/PCM with the HDS.
- Do the ECM/PCM idle learn procedure (see «ECM/PCM IDLE LEARN PROCEDURE»(ref-220572-S08440202922006022000000) ).
- Allow the engine to cool to between 23°F (-5°C) and 77°F (25°C).
- Start the engine, and let it idle 20 minutes.
- Check for Temporary DTCs or DTCs with the HDS. Are any Temporary DTCs or DTCs indicated? YES- If DTC P0116 is indicated, check for poor connections or loose terminals at the ECT sensor and the ECM/PCM, then go to step 1 . If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting. NO- Go to step 18 .
- Monitor the OBD STATUS for DTC P0116 in the DTCs MENU with the HDS. Does the screen indicate PASSED? YES- Troubleshooting is complete. NO- If the screen indicates FAILED, check for poor connections or loose terminals at the ECT sensor and the ECM/PCM, then go to step 1 . If the screen indicates NOT COMPLETED, go to step 15 and recheck.