What is the reason why the car EPC fault light is on?

Generally speaking, EPC lights have two possibilities. First, the throttle is dirty and needs cleaning. In another case, the brake light is not on, so it is necessary to check the brake switch and wiring. Also, due to the oil problem, the EPC fault light will also light up.

EPC indicator lights are more common in the public. After the key door is opened, the vehicle starts self-inspection, and the EPC indicator light will light up for a few seconds and then go out. If the vehicle does not go out after starting, it means that the mechanical and electronic system of the vehicle has failed.

Extended data:

In the past, the driver controlled the accelerator pedal according to the power demand of the engine, and the accelerator pedal controlled the accelerator opening through a steel wire rope. In EPC system, the former accelerator cable is replaced by the sensor of pedal device, and the engine control unit (ECU) calculates the optimal target accelerator opening according to the position data fed back by the sensor of pedal device, and sends a signal to the accelerator drive motor to make the accelerator rotate to this angle.

This method is superior to the cable acceleration control, because the electronic throttle knows the power demand of the engine by calculating and analyzing the input signal of the accelerator pedal position, and converts this information into the torque of the engine through various actuators.

When the engine speed needs to be adjusted due to safety, fuel consumption and other reasons, the engine control unit can adjust the position of the throttle valve without using the accelerator pedal. The advantage of this structure is that the control unit can limit the position of the throttle according to various requirements.

References:

Baidu encyclopedia -EPC