Advanced Diagnostics

Advanced Diagnostics

DTC P1116: Engine Coolant Temperature (ECT) Sensor 1 Circuit Range/ Performance Problem






General Description
Two engine coolant temperature sensors and one intake air temperature sensor are used by the engine control module (ECM)/powertrain control module (PCM). When the engine is stopped and enough time has passed, the temperature of the engine will equalize to the ambient temperature. When an inappropriate temperature is detected after comparing the temperature readings of each sensor, a malfunction in the corresponding sensor is detected and a DTC is stored.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status






Enable Conditions






Malfunction Threshold
A malfunction is detected if the following conditions are present after the engine has stopped and the ignition switch has been turned to LOCK (0) for at least 6 hours before restarting the engine:

- When the temperature difference between the IAT and ECT1 is 80 °F (44 °C) or more.
- When the temperature difference between the IAT and ECT2 is 51 °F (28 °C) or more.
- When the temperature difference between the ECT2 and ECT1 is 100 °F (56 °C) or more.

Driving Pattern
1. Turn the ignition switch to LOCK (0), and wait at least 6 hours.
2. Start the engine, and let it idle for at least 10 seconds.

Diagnosis Details

Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the ECM/PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.