What does it mean that FAW-Volkswagen Jetta dashboard shows EPC?

EPC is an engine electronic power control system.

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. 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.

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 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.

Extended data:

EPC function:

The accelerator pedal of the vehicle is connected with the accelerator of the engine through a steel wire, commonly known as the accelerator. The driver can directly open or close the accelerator by operating the accelerator pedal to accelerate or decelerate the vehicle. It is a mechanical control mode.

The advantage of this mechanical control method is that the parts are sensitive under normal circumstances, and what is obtained is what is needed. The disadvantage is that mechanical parts are prone to normal wear and tear, such as sticking and loosening.

Moreover, according to the driver's experience and perception, it is impossible to control the throttle valve to the ideal state, which leads to high fuel consumption during rapid acceleration, flameout of the rapid deceleration engine, and desperate acceleration when the vehicle slips. When cornering is insufficient, the accelerator pedal can't cooperate with the correction, and when cornering, the engine power output can't be controlled accordingly, which has potential safety hazards.

Therefore, luxury cars no longer use mechanical throttle control mechanism, but use electronic control system. There are a set of sensors on the accelerator pedal, which are used to sense the driver's willingness to accelerate and decelerate, and convert them into electrical signals and send them to the ECU control unit.

The control unit synthesizes other collected reference factors, such as steering angle, whether the tire slips, etc., and automatically obtains ideal data, and controls the correct output power of the engine by driving the electronic throttle.

Baidu encyclopedia -EPC