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)
  • Cooling system
  • engine coolant temperature sensor
  • thermostat
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 enabling conditions

Typical malfunction thresholds

Typical malfunction thresholds

Wiring diagram

Wiring diagram

Refer to dtc p0115

    Share this page:

    Other materials:

    Circuit description
    A flat type knock sensor (non–resonant type) has the structure that can detect the vibration in a wider band of frequency from about 6 khz to 15 khz and has the following features. Knock sensors are fitted on the cylinder block to detect the engine knocking. The sensor contains a piezoele ...

    Child restraint systems with a top tether strap
    1 Adjust the head restraint to the downmost position. 2 Secure the child restraint system using the seat belt or LATCH anchors. 3 Open the anchor bracket cover, latch the hook onto the anchor bracket and tighten the top tether strap. Make sure the top tether strap is securely latched. ` ...

    For safe driving
    For safe driving, adjust the seat and mirror to an appropriate position before driving. Correct driving posture Adjust the angle of the seatback so that you are sitting straight up and so that you do not have to lean forward to steer. Adjust the seat so that you can depress the pedals fully ...