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ECT Sensor Rationality (Drop Side) Monitor

OBD System Description - ECT Sensor Rationality (Drop Side) Monitor

System Description / Monitoring Procedure
ECM monitors ECT sensor to ensure that temperature has dropped to environmental temperature. After 5 hours (using timer module) from engine stop, the system wakes up ECM and measures ECT and IAT signal. If difference between ECT and IAT is more than the criteria, ECM will set DTC.

DTC Description / Detecting Condition / Confirmation Procedure

P1116
Refer to DTC P1116: Engine Coolant Temperature Circuit Performance at Engine Soaking

ECT Sensor Rationality (Drop Side) Monitor

ECT Sensor Rationality (Drop Side) Monitor:




Enable Conditions:




Typical Malfunction Thresholds: