DTC P0116: Engine Coolant Temperature Circuit Range/Performance Problem: DTC Detecting Condition

The purpose of this diagnosis is to detect a stuck coolant temperature signal. The diagnostic function checks whether after a variation of the calculated coolant temperature also a variation of the measured coolant temperature is detected. ECM sets DTC P0116 when the variation of measured engine coolant temperature from engine start is smaller than threshold while variation of calculated coolant temperature by ECM is greater than threshold. If this error code is set in the next driving cycle again, ECM illuminates the MIL. The diagnosis is performed only once per driving cycle.