| DTC Code | DTC Name |
|---|---|
| P0125 | Insufficient Coolant Temperature for Closed Loop Fuel Control |
DESCRIPTION
Refer to DTC P0115.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory |
|---|---|---|---|---|---|
| P0125 | Insufficient Coolant Temperature for Closed Loop Fuel Control | The engine coolant temperature does not reach the closed loop enabling temperature for 20 minutes (this period varies with the engine coolant temperature at engine start) (2 trip detection logic). |
|
Comes on | DTC stored |
MONITOR DESCRIPTION
The resistance of the engine coolant temperature sensor varies in proportion to the actual engine coolant temperature. The ECM supplies a constant voltage to the sensor and monitors the signal output voltage of the sensor. The signal output voltage varies according to the changing resistance of the sensor. After the engine is started, the engine coolant temperature is monitored by this signal. If the engine coolant temperature sensor indicates that the engine is not yet warm enough for closed loop fuel control, despite a specified period of time having elapsed since the engine was started, the ECM interprets this as a malfunction in the sensor or cooling system and stores this DTC.
MONITOR STRATEGY
| Frequency of Operation | Once per driving cycle |
CONFIRMATION DRIVING PATTERN
Leave the vehicle outside overnight.
Connect the GTS to the DLC3.
Turn the power switch on (IG) and turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
Read the DTC and record the freeze frame data.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
Check that the Coolant Temp is the same or less than Initial Engine Coolant Temp in the freeze frame data.
Turn the power switch off and wait for at least 30 seconds.
Turn the power switch on (IG) and turn the GTS on.
Put the engine in inspection mode (maintenance mode).
Start the engine.
Wait 21 minutes or more.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
Read the pending DTCs.
Tech Tips
If a pending DTC is output, the system is malfunctioning.
If a pending DTC is not output, perform the following procedure.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTC: P0125.
Check the DTC judgment result.
| GTS Display | Description |
|---|---|
| NORMAL |
|
| ABNORMAL |
|
| INCOMPLETE |
|
| N/A |
|
Tech Tips
If the judgment result shows NORMAL, the system is normal.
If the judgment result shows ABNORMAL, the system has a malfunction.
CAUTION / NOTICE / HINT
Tech Tips
If any of DTCs P0115, P0116, P0117 or P0118 are output simultaneously with DTC P0125, the engine coolant temperature sensor may have an open or a short circuit. Troubleshoot those DTCs first.
Read freeze frame data using the GTS. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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
CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0125)
Connect the GTS to the DLC3.
Turn the power switch on (IG).
Turn the GTS on.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
Read the DTCs.
| Result | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
If any DTCs other than P0125 are output, troubleshoot those DTCs first.
| B |
|
GO TO DTC CHART Click here |
| A |
|
INSPECT THERMOSTAT
Inspect the thermostat (thermostat opening temperature).
| Result | |||
|---|---|---|---|
|
| NG |
|
REPLACE THERMOSTAT Click here |
| OK |
|
CHECK COOLING SYSTEM
Check for defects in the cooling system that might cause the system to be too cold, such as abnormal cooling fan operation or any modifications.
Tech Tips
Perform "Inspection After Repair" after replacing the engine coolant temperature sensor.
| Result | |||
|---|---|---|---|
|
| OK |
|
REPLACE ENGINE COOLANT TEMPERATURE SENSOR Click here |
| NG |
|
REPAIR OR REPLACE COOLING SYSTEM |