DTC P0125-00: Insufficient Coolant Temperature For Closed Loop Fuel Control: General Description

An Engine Coolant Temperature Sensor (ECTS) monitors the temperature of the coolant. This input is used by the ECM/PCM for engine control and as an enabling criteria for related diagnostics. The air flow coming into the engine is accumulated and used to determine if the engine has been driven within conditions that would allow the engine coolant to heat up normally to the thermostat regulating temperature. If the coolant temperature does not reach regulating temperature of the thermostat, diagnostics that use engine coolant temperature as enabling criteria, may not run when expected.

This DTC will set when there has been excessive time to reach a minimum coolant temperature required for closed loop fuel control.