Hi,My epc light goes on, stays on for at most a day and then dissapear again. This problem repeats itself often.

have scanned for trouble code --vehicle went into limp mode and now protection mode [protecting you and itself --https://www.schworervolkswagen.com/blog/how-to-fix-epc-light-on-a-volkswagen/

That sounds like a bad connection. Check all connections for the EPC system from the accelerator pedal TPS to the throttle body itself. If that fails you could have a wire in the loom that is broken and makes inertmitent contacts.

Scan for codes.

The airbag light on the dashboard comes for few reasons, either there is a bad connection or connection came loose but than the light would stay on at all times, if it comes periodically than I would look up to the owner's manual and also find the airbag check label inside the car as it might be faulty or in need of replacement. The danger is that if it is faulty it can blow up by itself or in case of accident (hope none happens) it will malfunction.

Check the connector at the pedal.

EPC refers to the drive by wire system. This system, generally speaking, encompasses the throttle pedal and its position sensors (it needs to know where your gassin' foot is) and the throttle body.

Most likely, the EPC light and its associated faults for this scenario are a symptom, not the problem. Meaning the actual root cause is causing the no-start/no crank issue AND fault codes related to the EPC system.

And the most likely root cause is an ignition switch, NOT the engine speed sensor.

With a bad engine speed sensor, the car will still crank all damn day (or until the battery dies) but the car won't start.

If you get a no-crank issue, and then it eventually starts either with or without an EPC light, again, the most likely problem is the ignition switch. Not the starter, not the battery (though the battery proper and the cable connections must be perfection itself to rule them out.) You can get these issues with a visually perfect but still faulty battery connection.

Dear produceqa_de,

I am not entirely familliar with this particular model, although in some similar models that I have worked on The epc (on deisel models) usualy indicates a problem with the particle filter.

This means that if your car has a particle filter and it has not reached a temperature that it can clean itself for a few months, it may become clogged and cause a restriction for the engine.

If you take your car to an audi dealer the mechanic will be able to do a quick test to confirm and he may then be able to overide the cleaning process and clean the filter. I would advise that this is done asap as dammage may be caused from very high exhaust temperatures.

Reguards Luke.

make sure the gas cap is tight. it may take driving for a week for the light to go out.

I would suggest you check oil levels etc. Generally these cars suffer from the air mass meter / air sensor problems aswell as coil problems too. Did you ever get a solution to the problem?

Just a coincidece but the most common fault the brake light switch