P0125

2UR-FSE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0125: Insufficient Coolant Temperature for Closed Loop Fuel Control
P0125 - Insufficient Coolant Temperature for Closed Loop Fuel Control

DESCRIPTION

The closed-loop (air-fuel ratio feedback fuel control) begins when the engine coolant temperature (ECT) reaches the closed-loop enabling temperature.





MONITOR DESCRIPTION

Diagnosis trouble code (DTC) P0125 is designed to detect insufficient ECT for the closed-loop.

If the ECT does not reach the closed-loop enabling temperature when a specified period of time elapses, the ECM interprets this as a malfunction. When this malfunction is detected in consecutive driving cycles, the ECM illuminates the malfunction indicator lamp (MIL) and sets the DTC.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





WIRING DIAGRAM

Refer to DTC P0115 P0115.

INSPECTION PROCEDURE

HINT
- If DTC P0115, P0116, P0117 or P0118 are set simultaneously with DTC P0125, the Engine Coolant Temperature (ECT) sensor may have an open or short circuit. Troubleshoot those DTCs first.
- Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE

1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0125)

(a) Connect the Techstream to the DLC3.

(b) Turn the power switch on (IG).

(c) Turn the Techstream ON.

(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

(e) Read DTCs.

Result





HINT
If any DTCs other than P0125 are output, troubleshoot those DTCs first.

B -- GO TO DTC CHART SFI System
A -- Continue to next step.

2. INSPECT WATER INLET WITH THERMOSTAT

(a) Remove the water inlet with thermostat Removal.

(b) Check the valve opening temperature of the thermostat.

Standard:

80 to 84°C (176 to 183°F)

HINT
In addition to the above check, confirm that the valve is completely closed when the temperature is below the standard.

NG -- REPLACE WATER INLET WITH THERMOSTAT Removal
OK -- Continue to next step.

3. CHECK COOLING SYSTEM

(a) Check for defects in the cooling system that might cause the system to be too cold, such as abnormal radiator fan operation or modifications.

NG -- REPAIR OR REPLACE COOLING SYSTEM

OK -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR Removal