rickyguy

Hey guys
bought my first Audi recently. It’s a 2009 Audi s5 coupe (v8 model) I was driving around recently and all of a sudden while I was on the highway, my parking brake malfunction light and esp light came on and stayed on. I’ve been driving it since and I don’t feel any difference. Just curious to see why the lights came on. I’m hoping for it to be a wiring issue. But if any of you guys know what’s going on or had the same issue let me know in the comments.
Much appreciated
Thank !!

RossGA

I had a weird issue with a failing fuel pump that caused similar symptoms.

What would happen, is I would first get a CEL, then a few miles later I would get the ESP and parking brake malfunction light. Then, just a few miles later, the car would start running rough. I could clear codes, and it would run fine for a while. Within 10-20 miles, symptoms started returning

What was happening, was the passenger side high pressure pump was failing, and pulling too much electrical current through a circuit that also supports functions related to the parking brake and ESP controls. As the pump got worse, it would actually blow a fuse that is located on the top of the motor (NOT in the fuse box). Once it got bad enough to blow the fuse, we were able to isolate everything on that circuit and ended up replacing that high pressure pump, and it's been running great since.

I really don't know if this has anything to do with your problem, but I can tell you there is a fused ECU control module on the top of the motor that supports ESP, electronic parking brake, and fuel pump (passenger bank (there are 2 pumps)) functions; and having one failing component on that circuit (in my case, a fuel pump) caused all components on that circuit to throw error codes.

jschrauwen

I believe this has been covered before. This may be part of a TSB and a recall.
Have you done a TSB search for your VIN?

SloopJohnB@mac.com

there were a few failures on the C5 V8 A6s...

Itjohnnie

I just started experiencing the same problem with the same car. Its happened a few times now and then seems to go away on its own shortly after it lights up. I had the codes checked out and it listed a communication error. Did you ever discover and resolve the problem?
Appreciate the help!

jschrauwen

As I already mentioned, this is covered under a TSB which evolved into a recall for the power supply unit that supplies power for these systems and the passenger's airbag control.
Have you searched TSB's and recalls for your car using your VIN on audiusa?

NOFX

I've had this exact problem and it wasn't related to TSB. Turned out that while putting the cabin filter in under glove box a connector got knocked loose and needed to be reconnected. Once reconnected both warnings went away.

NOFX

Sorry need to retract my last post. I had an airbag and parking brake warning triggered by the connector near cabin filter. Sorry.

Itjohnnie

Thank you all. Unfortunately, AudiUSA only shows one unrelated outstanding recall related to Catalysts. I will have them check for other related TSB when I bring the car in to have the recall addressed.