Toyota Corolla (E120): Circuit description
Refer to dtc p0115
|
Dtc no. |
Dtc detection condition |
Trouble area |
| P0125 | If the engine coolant temperature (ect) was less than –6.6 °C (20 °F) when starting the engine, and 20 minutes after the engine start, the ect sensor still indicates below 20 °C (68 °F) |
|
| If the ect was between –6.6 °C (20 °F) and 10 °C (50 °F) when start, 5 minutes after the start, the ect sensor still indicates below 20 °C (68 °F) | ||
| If the ect was greater than 10 °C (50 °F) when starting the engine, and 2 minutes after the engine start, ect sensor still indicates below 20 °C (68 °F) |
Monitor description
The engine coolant temperature (ect) sensor is used to monitor the temperature of the engine coolant. The resistance of the sensor varies with the actual coolant temperature. The ecm applies a voltage to the sensor and the varying resistance of the sensor causes the signal voltage to vary. The ecm monitors the ect signal voltage after engine start–up. If, after sufficient time has passed, the sensor still reports that the engine is not warm enough for closed–loop fuel control, the ecm interprets this as a fault in the sensor or cooling system.
Example: the engine coolant temperature was 0 c (32 f) at engine start. After 5 minutes running time, the coolant temperature sensor still indicates that the engine is not warm enough to begin air–fuel ratio feedback control.
The ecm interprets this as a fault in the sensor or cooling system and will set a dtc.
Monitor strategy

Typical enabling conditions

Typical malfunction thresholds

Wiring diagram
Refer to dtc p0115
Other materials:
Starting the engine
1 Continuously variable transmission: Ensure that the shift lever is in P and
depress the brake pedal.
Manual transmission: Shift the shift lever to N and depress the clutch pedal.
2 Touch the Toyota emblem side of the electronic key to the engine switch.
When the electronic key is detected, a ...
Inspection
1. Inspect driver’s door lock
Inspect the door lock motor operation.
Standard:
If the result is not as specified, replace the door lock assembly.
Inspect the door lock and unlock switch continuity.
Standard:
If the result is not as specified, replace the door lock assem ...
Inspection procedure
1 Inspect shift solenoid valve(sl)
Remove the shift solenoid valve sl.
measure the resistance according to the value(s) in the
table below.
Standard:
Connect the positive (+) battery lead to the solenoid connector
terminal, and the negative (–) battery lead to the
so ...


