What does the EPC light mean in an Audi?

[SanNaomi]

The EPC warning light may illuminate during the power-on self-test or under other circumstances. The main reasons are: The power-on self-test is an indication that the vehicle is checking the status of all sensors before driving. Generally, if the engine is not started, the light will turn off by itself after about 3 seconds. If the EPC light remains on after the vehicle is started or illuminates under other circumstances, the possible causes include faults in the engine intake system, throttle valve, fuel system, engine, ECU control unit, or brake lights. The following are detailed explanations of the causes and solutions for the EPC light illuminating under other circumstances: Engine intake system fault: The EPC light may come on if the engine intake is obstructed or insufficient. You can open the intake manifold switch valve cover, place a listening rod against the switch valve, start the engine, and repeatedly press the accelerator pedal to clear the obstruction. Throttle valve fault: Carbon buildup is a common issue with the throttle valve. Additionally, dirt accumulation can affect intake and trigger the light. You can remove the throttle position sensor and install a new one. Fuel system fault: Issues such as substandard fuel, fuel deterioration, or poor fuel atomization can cause the light to illuminate. Use the appropriate fuel grade for your vehicle. Engine fault: Insufficient engine pressure or problems with the intake valves can also trigger the EPC light. Clean carbon deposits from the affected areas. Anti-theft system fault: If the anti-theft controller is incompatible with the engine electronic controller, the anti-theft system may prevent the engine from functioning properly, and the engine fault light may also illuminate. Visit a repair shop or dealership for assistance. ECU control unit fault: Issues such as signal interference or false alarms from the onboard computer can occur. Reprogram the ECU data. Brake light fault: If the brake lights are not working, the brake switch is faulty, or the brake wiring is defective, visit a repair shop or dealership to replace the brake lights. If the EPC light comes on, the owner can first try turning off the engine and restarting it to see if the light remains illuminated. If it does not, there may be no issue, and the light may have been triggered by a temporary condition. If the light stays on or frequently illuminates, drive to the nearest repair facility for professional diagnosis and timely resolution of potential safety hazards. The full English 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 mainly includes controllers and sensors related to the powertrain. When sensor data is abnormal, the EPC system takes predefined actions to address the issue. Common EPC warning lights are typically two colors: yellow and red. A yellow EPC light indicates a fault, but the vehicle can still be driven cautiously to a repair facility. A red EPC light indicates a serious issue, and the vehicle should be pulled over immediately. Contact a professional for repairs, as continued driving may damage core components or compromise safety.