Audi A8L MMI Car Button Reboots

Force reboot . Press the setup button and the centre knob and the right top knob together ,as soon as you leave the 3 button in will reboot

it sounds like you had a disruption in power and it may need to be reintroduced to the car with a diagnostic computer.

Sorry to state the obvious, bit just in case, have you checked to be sure the screen is turned on? Press and hold the volume knob for a few seconds. There is also a display off button on the dash to rt. of the display unit.

If all are on, try resetting the unit:
http://www.youtube.com/watch?v=vEGuqiS3EGU

Check in hidden green menu if you have everything configured as it should be.
Details at http://mr-fix.info/

I bet that rear screen washer lines are broken and fluid damaged electronic under trunk trim.

Look at your MMI in there go to settings and check that your locking is to all doors in the MMI you can set what you like and what door to lock your Drivers door lock may be switched off just change it to on and it will work.

I have seen this before and found the Dash insert is defective, Go to address 17 and carry out a final control segment test for the dash when the fault occurs also make sure there are no battery management fault codes.

Restriction of functions
The following are deactivated in the event of
active load intervention by the battery and
energy management system:
- Interior lighting
- Sunroof
- Light/humidity sensor
- Interior mirror

Check you ambient in car lighting settings in the mmi user functions for current settings

Park brake uses 58d terminal and the rest use 58s terminal from memory

No solution, same problem, but had many strange moments: 4 months ago during 100 kms or so it stopped, then suddenly came back, and worked ever since. A few days ago, it started happening again: NAV stuck, then radio dead, and gradually the rest disappeared. I did a Reset, and since that moment I see the intro-screen and then it goes black. Hitting the TEL button is somehow also a Reset...

Do the previous 2 posters have anything to report on this matter? It would be VERY welcome!

Thanks,
Jeff

you nid mmi circuit board replaced,happened to me after spilling coffee,audi wanted to replace the whole thing with a new mmi system for a lot of money, but Ifound someone to change circuit board for abt £200 which is not bad,the only thing is you have to take out the whole centre console and air con unit and armrest off,so u nid some one who knows how to do it.check on tyresmoke and post from there,will respond and give you more info.The previous owner must have spilt something and panicked and sold the car without being honest.It sucks..........