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DTC P0125

DTC P0125

Insufficient coolant temperature for closed loop fuel control

DETECTION CONDITION

The PCM monitors the ECT after cold engine start. If the ECT does not reach the specification in a certain period, the PCM determines that the coolant temperature for closed loop fuel control is insufficient.

Diagnostic support note

This is a continuous monitor (engine cooling system).
The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
FREEZE FRAME DATA (Mode 2/Mode 12) is available.
The DTC is stored in the PCM memory.

POSSIBLE CAUSE

MAF sensor malfunction
ECT sensor malfunction
PCM malfunction

DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA (MODE 12) AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED Have the FREEZE FRAME DATA (Mode 12) and DIAGNOSTIC MONITORING TEST RESULTS (engine cooling system related) been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA (Mode 12) and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
2	VERIFY RELATED REPAIR INFORMATION AVAILABILITY Verify related Service Bulletins and/or on-line repair information availability. Is any related repair information available?	Yes	Perform repair or diagnosis according to the available repair information. If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	VERIFY CURRENT INPUT SIGNAL STATUS Start the engine and warm it up completely. Access the ECT PID using M-MDS. (See ON-BOARD DIAGNOSTIC TEST ). Is the ECT PID more than 70°C {158°F}?	Yes	Intermittent concern exists. Perform the "INTERMITTENT CONCERN TROUBLESHOOTING". (See INTERMITTENT CONCERN TROUBLESHOOTING ).
3		No	Go to the next step.
4	INSPECT MAF SENSOR Inspect the MAF sensor. (See MASS AIR FLOW (MAF) SENSOR INSPECTION ). Is there any malfunction?	Yes	Replace the MAF/IAT sensor, then go to Step 6. (See MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REMOVAL/INSTALLATION ).
4		No	Go to the next step.
5	INSPECT ECT SENSOR Inspect the ECT sensor. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION ). Is there any malfunction?	Yes	Replace the ECT sensor, then go to the next step. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION ).
5		No	Go to the next step.
6	VERIFY TROUBLESHOOTING OF DTC P0125 COMPLETED Make sure to reconnect all disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE ). Access the ECT PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST ). Wait until the ECT PID less than 20°C {68°F}. Start the engine and warm it up completely. Perform the Pending Trouble Code Access Procedure. (See ON-BOARD DIAGNOSTIC TEST ). Is the PENDING CODE same as the DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION ).
6		No	Go to the next step.
7	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE ". (See AFTER REPAIR PROCEDURE ). Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE ).
7		No	DTC troubleshooting completed.