Electronic Parking Brake problem

[Conehead]

Hi all, I have a 2004 4.2 Quattro with what seems to be a serious issue. The parking brake would not release on the right rear wheel so called out AA who said it was a siezed caliper but wound it back so that I could move the car. Today I took it to a local garage who used vcds to try and sort it out but also said the caliper has not seized,

it is coming up with a couple of faults: 01487 System Function Test Fail, 02433 Right Rear brake motor open circuit and also the EPB control keeps dropping out with no comms.

I have said about the wire having a problem fraying on this years model where it connects to the caliper which they checked and said it was okay.

Any suggestions as to what to try or it could possibly be?

Cheers for now

 

[rawtor51]

May be the motor on the calliper. Although sealed from the factory dirt does get in over time and the gearing can be chewed up causing it to not release thats why a manual wind back works but not the electronic through vag com

 

[Conehead]

Cheers for that, will try that in morning.

 

[Conehead]

I have checked the wiring back further and it is all okay. The button in the car operates the nearside brake with no problem so guess that the switch is okay along with the EPB Module as must be sending a signal to the brakes.

Car is a 2004 C6 Model, 4.2 Quattro with 101000 miles on it. MOT carried out back in January and no other problems with brakes up to this point.

Any other suggestions would be very helpful

 

[rawtor51]

Yep the motor on the calliper.....

 

[Conehead]

I have just had report from garage saying that the OS brake has 2v at motor and the NS nothing. With this in mind as the NS one is working and the OS not it looks like the motor is getting the power all the time hence not releasing like the NS. So could this be harness, handbrake switch or the dreaded EPB Command Module.

 

[saxonblue]

I have just gone through a lot of problems with the hand brake on my car, have a look for my thread. funny enough its a 2004 motor as well. I replaced ALL the parts that go along with the brake, for example (sit down....this go's on a bit ) both rear callipers, new handbrake switch, new wiring harnesses , oh and discs and pads,
now as you can guess, that little lot was not cheep, But here's the thing- after all that work was done, the ****** thing still went mad, working one side but not the other one, then the other side would start to work, then nothing at all
vag com and the bloke I was using to sort my car out all went mad over a long period of time trying to sort this out, turns out that yes my wiring was goosed, although you wouldn't have noticed, there was a small brake in the wiring, also after that was all sorted out, the new/used handbrake switch was faulty,
my advice to you is this, get the hand brake switch checked out first, get someone with vag-com to try to open or close the calliper, if this wont work have a look if there's a signal going to the calliper, and look at the switch itself, mine looked fine, but on closer inspection it was sticking just a little, that was throwing up errors all over the place, and the callipers could not respond. a new switch (well new to me) off eBay
for £35 sorted it out, but be warned, disconnect the battery before doing anything with new switch.
sorry its so long whined but I hope this helps :thumbsup:

 

[Conehead]

Thanks for that, I asked garage to check switch and they said they can see it is working via vcds but have asked them to change it anyway. I took car tonight off them as needed to get home and not happy to report that neither brake working now.

 

[saxonblue]

hummm,,:ermm not good, my switch was playing up big time, it looked as though it was working fine, it lit up ok and did work the callipers ok, then it wouldn't work at all,
it was doing my head in, you could try pulling the 2 fuses out in the boot for a while, that did work on mine for a short time after all the other stuff was replaced, or do a reset by disconnecting the battery

 

[Tank.]

suppose wiring and switches are cheaper than a new caliper or two but this leads for a little scary reading, just bought an 05 plate myself, mind you ive got bigger problems than brakes at the moment

 

[Conehead]

Which two fuses, I know about the 30A one but what other one?. Lovely car when it is all working but ****** expensive bills when its stops though

 

[gupsterg]

Dunno if applicable but there is a software update which exists for early EPB modules where EPB fails to disengage / has various DTCs , google uberlame a6 and look in brake section.

I will try to find upto which VINs this applies.

Truly agree conehead luvly cars but when they chew money it's like PAC man in super speed motion!

 

[saxonblue]

I removed to 2 fuses at the bottom, as in both the 30 amp ones.
the guy I get my motor fix at told me that software up dates are ok, but sometimes they can stuff thing up more then before,