Diagnostic Aids
Check for the following conditions:
- If a DTC P0106 and P0121 are also set, the malfunction may be in the sensor ground circuit.
- Check for the proper operation of the engine cooling system, including the correct coolant level.
- A faulty thermostat that stays open slightly can cause a DTC P0116 to set in cold weather when the vehicle is started and let sit while warming up. Replace any suspect thermostat.
- Use the Temperature vs Resistance table in order to evaluate the possibility of a shifted (incorrectly calibrated) ECT sensor. A shifted sensor may result in a DTC P0116. Refer to SENSOR OPERATING RANGE CHARTS - TRUCKS article.
- Check for a faulty electrical connection to the PCM.
If a DTC P0116 is intermittent, driving the vehicle under the following conditions can verify whether the fault is present. Perform the scan tool clear DTC information function. Road test the vehicle while monitoring the DTC P0116 diagnostic on the scan tool under the Not Ran Since Code Cleared selection in the DTC Information menu. If a DTC P0116 appears in the Not Ran Since Code Cleared list, the P0116 diagnostic has not yet run. When the DTC P0116 does not appear in the Not Ran Since Code Cleared list, the P0116 diagnostic has run. If the MIL is NOT ILLUMINATED, and there is no PENDING DTC Status in DTC Information, the P0116 diagnostic has passed. DTCs MUST BE CLEARED in order to view the CURRENT STATUS of the Not Ran Since Code Cleared list. DO NOT FORGET that the Not Ran Since Code Cleared list only indicates that the test has run, not whether the test passed or failed. The DTC Information screen must be checked for CURRENT or PENDING status, in order to determine the outcome of the diagnostic test involved.
An intermittent malfunction may be caused by a fault in the ECT sensor electrical circuit. Inspect the wiring harness and components for an intermittent condition. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 2.0L & 2.5L TRACKER article. Repair any electrical circuit faults that were found.
If a DTC P0116 cannot be duplicated, the information included in the Freeze Frame data can be useful in determining the vehicle operating conditions when the DTC was first set.