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Home >> Lexus >> 2008 >> GS 450h >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTC P0010 - P0128 >> DTC P0125 Insufficient Coolant Temperature for Closed Loop Fuel Control >> Description
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DTC P0125 Insufficient Coolant Temperature for Closed Loop Fuel Control: Description

A thermistor is built into the Engine Coolant Temperature (ECT) sensor, of which the resistance value varies according to the ECT.

The structure of the sensor and its connection to the ECM are the same as those of the Intake Air Temperature (IAT) sensor.

DTC DETECTION CONDITION AND TROUBLE AREA REFERENCE

DTC No. DTC Detection Condition Trouble Area
P0125 Engine coolant temperature (ECT) does not reach closed-loop enabling temperature for 20 minutes (this period varies with ECT when engine start) (2 trip detection logic)
  • Engine coolant temperature sensor
  • Cooling system
  • Thermostat