DESCRIPTION
Refer to DTC P011511.
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DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory | Note |
---|---|---|---|---|---|---|
P012500 | 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 | SAE Code: P0125 |
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 engine cooling system and stores the DTC.
MONITOR STRATEGY
Related DTCs | P0125: Insufficient engine coolant temperature for closed loop fuel control |
Required Sensors/Components (Main) | Engine coolant temperature sensor Water inlet with thermostat sub-assembly Engine cooling system |
Required Sensors/Components (Related) | - |
Frequency of Operation | Once per driving cycle |
Duration | 69 seconds: Engine coolant temperature at engine start is (closed-loop engine coolant temperature - 8.33°C [46.994°F]) or higher 157 seconds: Engine coolant temperature at engine start is (closed-loop engine coolant temperature - 19.44°C [66.992°F]) or higher, and less than (closed-loop engine coolant temperature - 8.33°C [46.994°F]) 1200 seconds: Engine coolant temperature at engine start is less than (closed-loop engine coolant temperature - 19.44°C [66.992°F]) |
MIL Operation | 2 driving cycles |
Sequence of Operation | None |
TYPICAL ENABLING CONDITIONS
Monitor runs whenever the following DTCs are not stored | None |
All of the following conditions are met | - |
Thermostat fail (P0128) | Not detected |
Intake air temperature sensor circuit fail (P0112, P0113) | Not detected |
Engine coolant temperature sensor circuit fail (P0117, P0118) | Not detected |
Mass air flow meter circuit fail (P0102, P0103) | Not detected |
TYPICAL MALFUNCTION THRESHOLDS
Time until actual engine coolant temperature reaches closed loop fuel control enabling temperature | 69 seconds: Engine coolant temperature at engine start is (closed-loop engine coolant temperature - 8.33°C [46.994°F]) or higher 157 seconds: Engine coolant temperature at engine start is (closed-loop engine coolant temperature - 19.44°C [66.992°F]) or higher, and less than (closed-loop engine coolant temperature - 8.33°C [46.994°F]) 1200 seconds: Engine coolant temperature at engine start is less than (closed-loop engine coolant temperature - 19.44°C [66.992°F]) |
CONFIRMATION DRIVING PATTERN
HINT:
Click here
Click here
HINT:
Techstream Display | Description |
---|---|
NORMAL |
|
ABNORMAL |
|
INCOMPLETE |
|
HINT:
The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
WIRING DIAGRAM
Refer to DTC P011511.
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CAUTION / NOTICE / HINT
HINT:
PROCEDURE
1. | CHECK ANY OTHER DTCS OUTPUT (IN ADDITION DTC P012500) |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine / Trouble Codes.
(e) Read the DTCs.
Powertrain > Engine > Trouble Codes Result | Proceed to |
---|---|
DTC P012500 is output | A |
DTC P012500 and other DTCs are output | B |
HINT:
If any DTCs other than P012500 are output, troubleshoot those DTCs first.
B | GO TO DTC CHART |
|
2. | INSPECT WATER INLET WITH THERMOSTAT SUB-ASSEMBLY |
(a) Inspect the water inlet with thermostat sub-assembly (thermostat opening temperature).
Click here
NG | REPLACE WATER INLET WITH THERMOSTAT SUB-ASSEMBLY |
|
3. | CHECK ENGINE COOLING SYSTEM |
(a) Check for defects in the engine cooling system that might cause the system to be too cold, such as abnormal cooling fan operation or any modifications.
HINT:
Perform "Inspection After Repair" after replacing the engine coolant temperature sensor.
Click here
OK | REPLACE ENGINE COOLANT TEMPERATURE SENSOR |
NG | REPAIR OR REPLACE ENGINE COOLING SYSTEM |
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