The illumination of the EPC indicator light in a car can occur during the power-on self-test or under other circumstances. The main reasons are as follows: The power-on self-test is an indication of the vehicle's sensor status check before driving. Generally, if the engine is not started after powering on, the light will turn off by itself after about 3 seconds. If the EPC indicator light remains on under other circumstances or does not turn off for a long time after the vehicle is started, the possible causes include faults in the engine intake system, throttle valve, fuel system, engine, ECU control unit, or brake light. The following details the reasons and solutions for the EPC light illuminating under other circumstances: Engine intake system fault: When the engine intake is obstructed or insufficient, the EPC light will illuminate. You can open the intake manifold switch valve cover, place a listening rod against the intake manifold switch valve, and repeatedly press the accelerator pedal while starting the engine to clear any blockages. Throttle valve fault: Carbon buildup is a common issue with the throttle valve. Additionally, dirt on the valve body can affect intake, causing the indicator light to illuminate. The throttle position sensor can be removed and replaced with a new one. Fuel system fault: Issues such as substandard fuel, fuel deterioration, or poor fuel atomization can trigger the light. Choose the appropriate fuel grade for your vehicle model. Engine fault: Insufficient engine pressure or problems with the intake valve and other powertrain components can also cause the EPC light to illuminate. Carbon buildup in related areas should be cleared. Anti-theft system fault: If the anti-theft controller is incompatible with the engine electronic controller, the anti-theft system can prevent the engine from functioning properly, and the engine fault light may illuminate. Visit a repair shop or 4S store for assistance. ECU control unit fault: Issues such as interference with the vehicle computer signals or false alarms from the vehicle computer can occur. Reflash the ECU data if necessary. Brake light fault: If the brake light fails to illuminate or there are issues with the brake switch or wiring, visit a repair shop or 4S store to replace the brake light. If the EPC light illuminates, the owner can first try turning off the engine and restarting it to see if the light remains on. If it does not, there may be no issue, and the light could have been affected temporarily. If the EPC light stays on or frequently illuminates, drive to the nearest repair point for professional diagnosis and timely resolution of potential safety hazards. The full name of EPC is Electronic-Power-Control, which translates to electronic power control. Most people refer to it as the engine electronic stability system. The EPC system primarily includes controllers and sensors related to the powertrain. When sensor data is abnormal, the EPC system takes predefined measures to address the issue. The EPC indicator light typically appears in two colors: yellow and red. A yellow EPC fault light indicates that the vehicle can still be driven, but you should proceed slowly to a repair point for inspection. A red EPC fault light signifies a more serious issue, and you should pull over immediately and contact a repair professional. Continuing to drive could damage core components or compromise safety.
