bobgrice

I have been doing some research for the past few days on my issue, but have not found a post yet that more closely resembles my situation. I am sure there are posts out there, but I wanted to start my own thread to discuss with you more experienced folks.

Car: 2004 A8L

Issue: Sunroof drains backed up last week and I opened the door one morning to find a decent amount of water on the console/MMI controls. Car started and drove OK, but MMI screen would open every few minutes for around 5-10 seconds and play the radio, then shut off and the screen would retract. Could not "Accept" the warning using main **** click. There was also some weird map/dome light activity, but that settled down on the first day and has not been a problem since.

Did some research on MMI controls and removed that along with the parking brake switch, which also had failed.

Used isopropyl alcohol as a cleaning agent and carefully washed the boards. End product actually looked really good, especially given the amount of residue that was present on both the e-brake switch and MMI control board.

Reinstalled. Parking brake is fixed. Excellent. MMI system issue has changed slightly: Unit powers on, screen pops out and radio plays. I can control the volume with the steering wheel controls and the unit no longer turns off (let it play for around 5 minutes this morning). However, there are no lights on the controls and no buttons do anything - the screen still shows the warning, but I cannot dismiss it. I tried the three-button reset, but nothing happened, which makes sense, since I believe the whole unit is probably shot.

Herein lies my main questions: I can easily purchase a replacement control unit and install it and figured since it got pretty wet that's the main issue.

1. Does anyone feel strongly that simply replacing this control unit will completely solve the issue? How likely is it that this unit getting wet could have caused other issues, especially since the radio is currently functioning OK?

2. Will I have to remove CP after installing this unit? Is there any DIY way of doing this programming?

Thanks in advance to anyone taking a minute to respond.

MP4.2+6.0

Hi--


This really is not a unique scenario, or one that hasn't been posted on many times before, including exactly leaking onto controls. Just another version of Pepsi Syndrome for ones dumping soda or coffee on them. You did the usual try to save it steps. Logical next steps are:

1. Buy VCDS, which would tell you diagnostically what is going on and most likely exactly which part is problematic.
2. Skip #1 (which I can guess is where you are going since it seems like not done so far?) and roll dice that 95% it is the MMI control board.

Don't recall on CP. That should be searchable. CP is either mandatory trip to dealer or finding the relative handful of contacts scattered around world who can hack it remote.

JulianHicks

Hi Bob; since I presume you're talking about replacing the MMI panel with the buttons, this is NOT a 'control unit'. It's a board with connections to the MMI 'control head', which IS a control unit.

The panel [E380] is not subject to CP; the control head [J523] is.

Julian

ty4sound

I had the same exact problem with my 07 A8L and replaced the MMI board and all is well. I got mine from feabay for 199.95 make sure it for A8/S8. There a video on youtube on how the replace it. Also to get to the front sunroof drain plug you have to remove front wheeltire wells and on passager the washer bottle to clean drain off hose. The job is a lot easier than it look.

NEW MMI Control Circuit Board with Navigation for Audi A8 A8L S8 Quattro 06-08

bobgrice

Thanks to everyone for the excellent information!

bobgrice

Does anyone know whether the inexpensive board on epay, which shows it is for a '06-'10 A8/S8 will work on an '04 model year? The board looks similar enough at first glance.
Thanks in advance!

bobgrice

Later model replacement dropped in and solved the issue. I was hoping I would be able to swap the new board over to my plastic surround, but no dice. So, now I need to find a fingerprint start switch to fill the hole. Anyone have a dead one they'd like to get rid of? I'll pay postage and throw you a fiver for a craft beer at your favorite brewery.