Help: EPC fault code

**g75y** · 08-11-2009 04:52 AM

Recently after sending my car for servicing and oil change, I've had the EPC fault code come up when I start my car in the morning. The manual doesn't say what it is but onboard computer says don't drive past 4000rpm and the manual says to send in to authorised workshop to check asap.

But after I stop the car and restart the engine, the code goes away and car drives normally. This has happened twice since I got the car serviced.

Anyone experienced such problems or anyone know what it might be? I heard EPC has to do with the emission / fuel-air mixture??

Thanks!

**Blake P** · 08-11-2009 08:45 AM

Here's an answer I got by running a quick google search:

EPC means Electronic Power Control. This basically means there is no accelerator cable from the gas pedal to the throttle valve unit-power control is done electronically through sensors and other electronic devices, just to put it simple for your understanding.
Whenever any of the sensors incl. the brake light switch develops a fault, the EPC light comes on (normally off when driving unless there is a fault) to warn you of a potential fault. You may experience driveability problem during such times.
As the fault is purely electronic type, you will need a scan tool from a competent shop to tell what fault codes are in the system and the required remedy.You could do a basic check first by watching if the brake lights work or not?
I hope this helps.

Source(s):
VW/Audi Master tech-10 yrs exp.

**blkb7** · 08-11-2009 08:00 PM

i have and had the same problem for about a month now. when i got it scanned it came back as a fryed oil pressure sensor. was supposed to have had it changed out already but riverside has/had issues and they still haven't ordered it so i gotta have it done some where else. tomorrow actually, i'll let you know if it comes up as something else and how the dealer took care of it.

**g75y** · 08-12-2009 01:15 AM

Thanks a lot Blake and blkb7. Will keep you guys posted on what it is. Looks like its a generic code to alert that one of the sensors is not working.

Brake lights seem to work fine so don't think its that. Hope its nothing too major.

**blkb7** · 08-12-2009 06:05 PM

so my car went in today and they scanned it. came back that the connection was lose to the oil pressure sensor and n75 valve. so he says i drove it around after i got it back at different speeds and rpms in different gears at complete randomness since that's how the fault would appear. so far no fault. so as of right now i guess it's been fixed. i'll really test it out on my way to work tomorrow. the other thing i noticed was the whole time with the epc fault and 4krpm limit was when i would go check my oil levels on mmi, it wouldn't ever show up. but now it does. so see if you have that same issue.

the test they did was fault trace & test fuel sensor, so i guess you would probably want to get it scanned and see what pops up.

out of curiosity, is yours a 6psd??

**g75y** · 08-13-2009 05:01 AM

Thanks. Mine is an auto tiptronic

What do you mean when you check oil levels on mmi? The error code would come up when you did that? Or you saying that checking oil level on mmi would highlight that there is a problem?

Originally Posted by blkb7

so my car went in today and they scanned it. came back that the connection was lose to the oil pressure sensor and n75 valve. so he says i drove it around after i got it back at different speeds and rpms in different gears at complete randomness since that's how the fault would appear. so far no fault. so as of right now i guess it's been fixed. i'll really test it out on my way to work tomorrow. the other thing i noticed was the whole time with the epc fault and 4krpm limit was when i would go check my oil levels on mmi, it wouldn't ever show up. but now it does. so see if you have that same issue.

the test they did was fault trace & test fuel sensor, so i guess you would probably want to get it scanned and see what pops up.

out of curiosity, is yours a 6psd??

**blkb7** · 08-13-2009 06:11 PM

i drove to work and around after, roughly 50 miles and no faults so i guess it's fixed. as for the checking the oil, in the period of time i had the random epc light go on or even when it was off, when i would check the oil level through mmi, it would say no information is available. basically i was never able to check the oil level, but since i've had it fixed i am able to again. was just wondering if you had that same issue too.

**g75y** · 08-19-2009 07:04 AM

Just back from the service centre - apparently its one of the sensors for the cylinder which has been replaced. Hope thats all it is. Thanks for your help.

**blkb7** · 08-19-2009 08:05 AM

nice, just a sensor. i've had no issues since. hopefully u too as well.

**ViToMiNs090** · 04-18-2010 12:10 PM

Every once and awhile, when I try to start my car, the ignition does not turn and the car will not start. I get the same EPC light in my dash and the steering wheel and brake pedal lock. The only way to get the car to start, is it I put the car in reverse and let it roll down my driveway a bit. Then after I put it back in park, the car starts right up.

Has anyone else experienced this and figured out what the problem is? I have brought the car in for 2 services, and when they hook it up to the computer, they said there was no problems. It only occurs once and awhile, but if I and parked on an incline, it is a real pain in the ass to get it started.

I have a 2009 A4 with tiptronic and the push key ignition, not push button...Any kind of response would be greatly appreciated.

**ViToMiNs090** · 04-20-2010 07:20 AM

BUMP...

Any ideas guys??

**ViToMiNs090** · 05-05-2010 08:32 AM

More problems here.

The car keeps doing this every once and awhile. Foot on the brake, push the key in, electronics and everything turn on, but the ignition does not turn. I do not hear the engine at all!

The steering wheel locks and the brake locks. The only way to get it to start is if I put it in neutral and let it roll for a bit and then put it back in park and it starts right up. I brought it in, and they kept the car for almost a week. It started up fine every time they tried and there were no error codes, so they basically just gave it back and shrugged their shoulders. 3 days after getting it back, I had the same problem. This has happened on flat surfaces and inclines.

I now had to buy my self the VAG COM wire so that I can hook it up to a computer myself next time it happens, hoping that it will throw some kind of codes at me when the car won't start.

If anyone could provide any assistance, I would greatly appreciate it. I have only 1 Audi dealer in my area and they are the absolute worse. Never clean the car when I bring it in for service and never have a loaner available. I love Audi, but this problem along with the awful dealer in my area, makes me want to just trade in my car for something else :(

**jenkins0009** · 02-24-2015 02:57 AM

2010 audi a4.
I started merging onto the highway and before I reached 60 mph, my car started shaking horribly and two dashboard lights lit up (ignition and EPC). I pulled over to the side of the road and the car was still shaking pretty bad, even while in park. I turned it off, waited a few minutes, and started it up again. It started fine, but continued to shake like crazy. I was actually on my way to the audi dealership (Lexington KY) for a different issue so I limped onward. I drove 45 mph on the 70 mph highway with my flashers on. The dealership said that three of my four ignition coils had gone bad. I had the certified preowned warranty still in place, so I only had to pay my deductable ($85). Out of curiosity, I asked what they would charge if I didn't have the warranty... $390.

After they replaced the 3 coil packs, the car started up fine and no longer shook. All faults were gone. I'll update if anything changes.