DTC P0116: ECT Sensor Circuit Range/Performance Problem (2003-2005 models)

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?
1. YES- Go to step 3.
2. 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?
1. YES- Intermittent failure, system is OK at this time. Check the thermostat and the cooling system.
2. 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?
1. YES- Intermittent failure, system is OK at this time. Check the thermostat and the cooling system.
2. NO- Go to step 10.
Turn the ignition switch OFF.
Replace the ECT sensor (see ECT SENSOR REPLACEMENT ).
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 ).
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?
1. 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.
2. NO- Go to step 18.
Monitor the OBD STATUS for DTC P0116 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
1. YES- Troubleshooting is complete.
2. 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.