EPC light for the 2004 Golf 2.0 L, the light is on. I do have to get the Catalytic Converter changed for a recent recall...

EPC Stands for "electronic power control". Almost any sensor fault on the car can trigger an EPC. Take it to the dealer (or local auto parts store) for a diagnostic as the EPC fault light is not very "illuminating" on its own. The EPC light came on in my wife's Beetle and it quit shifting. I cleared the code. And no more problem. Just goes to show, the EPC light is for any problem.