What can cause a P0125 code?
What are the Possible Causes of the P0125 Code?
- Defective or damaged ECT sensor.
- Damaged coolant temperature sensor wiring or connection.
- Low coolant levels.
- Coolant leaks.
- Thermostat is stuck open.
- Damaged ECM.
What causes insufficient engine temperature?
The most common reasons for the temperature to remain low include: A thermostat stuck open. A bad engine coolant temperature sensor. A locked fan clutch.
What does closed loop fuel control mean?
In a nutshell, closed loop is where the engine operates with a feedback loop. A sensor closes the loop. The sensor in question is a lambda sensor, also known as an oxygen sensor or air/fuel ratio mixture sensor. In closed loop mode, the engine listens to the lambda sensor to adjust fuel/air mixture.
Why does coolant get low in winter?
Cold Temperatures The lower the external temperature, the more coolant particles contract. Sometimes, this is enough to lower coolant levels and trigger the sensor. This is especially likely if your vehicle has been sitting outside for days without use during the winter months.
What happens if coolant is below minimum?
Low coolant can sometimes cause a head gasket on your engine block to blow. If this happens, you may notice smoke emitting from the engine or tailpipe, a loss of power, engine knocking sounds, or decreased efficiency.
Is open loop better than closed loop?
Difference between Open Loop and Closed Loop Control System
| Open Loop Control System | Closed-Loop Control System |
|---|---|
| The consistency is non-reliable | The consistency is reliable |
| The accuracy of this system mainly depends on the calibration | These are accurate due to feedback |
What sensors are used in closed loop?
In a closed-loop system, an oxygen sensor, along the exhaust path, measures the oxygen to provide feedback regarding the air/fuel mixture and automatically adjusts the amount of fuel required for starting. As the engine temperature rises, sensors provide output to adjust the air/fuel for running.
What is the DTC code for insufficient coolant temperature?
P0125 is a diagnostic trouble code (DTC) for “Insufficient Coolant Temperature for Closed Loop Fuel Control”.
What is closed loop fuel mixing?
When the engine heats up to its operating temperature, your car switches over to Closed Loop. In this system, the air and fuel mixture is computed based on the conditions in your vehicle as determined by sensors in the engine.
What happens when the engine is in closed loop mode?
Once the engine reaches operating temperature, the ECM goes into “closed loop” mode, using the AFR sensors to maintain performance and fuel economy. Generally, the ECM expects that the engine will take a certain amount of time to reach proper operating temperature, but this can vary, depending on climate, coolant level, and thermostat function.
What happens if there is insufficient coolant in the system?
If there is insufficient coolant in the system, the engine may not warm properly. If the ECT is not in contact with the coolant, it will not read the temperature. Similarly, if there is a problem with the ECT sensor or circuit, the ECM may not receive a true indication of the engine coolant temperature.