DTC Troubleshooting

Control System DTCs

DTC Troubleshooting: P0116

DTC P0116 : ECT Sensor 1 Circuit Range/Performance Problem

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information How To Troubleshoot The Fuel And Emissions Systems.

1. ECT sensor 1 check:

ECT sensor 1 check
-1. Turn the ignition switch to ON (II).

-2. Check ECT SENSOR 1 in the DATA LIST with the HDS.

Is about 176 °F (80 °C) or more indicated?
-YES- Note the value of ECT SENSOR 1, then go to step 3.
-NO- Note the value of ECT SENSOR 1, then go to step 2.

2. Problem verification (low temperature):

Problem verification (low temperature)
-1. Note the value of ECT SENSOR 1 in the DATA LIST with the HDS.

-2. Start the engine. Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on, then let it idle.

-3. Check ECT SENSOR 1 in the DATA LIST with the HDS.

Does ECT SENSOR 1 change 18 °F (10 °C) or more?
-YES- Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at ECT sensor 1 and the ECM/PCM.
-NO- The failure is duplicated. Replace ECT sensor 1 ECT Sensor 1 Removal and Installation, then do the repair verification.

3. Problem verification (high temperature):

Problem verification (high temperature)
-1. Turn the ignition switch to LOCK (0).

-2. Open the hood, and let the engine cool for 3 hours.

-3. Turn the ignition switch to ON (II).

-4. Check ECT SENSOR 1 in the DATA LIST with the HDS.

Does ECT SENSOR 1 change 18 °F (10 °C) or more?
-YES- Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at ECT sensor 1 and the ECM/PCM.
-NO- The failure is duplicated. Replace ECT sensor 1 ECT Sensor 1 Removal and Installation, then do the repair verification.

Repair verification:

-1. Turn the ignition switch to ON (II).

-2. Reset the ECM/PCM with the HDS How To Troubleshoot The Fuel And Emissions Systems.

-3. Do the ECM/PCM idle learn procedure. ECM/PCM Idle Learn Procedure

-4. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0116 indicated?
-YES- Check for poor connections or loose terminals at ECT sensor 1 and the ECM/PCM, then go to step 1.
-NO- Troubleshooting is complete. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.