MMI keeps restarting
 

Just driven 3 miles, with the MMI constantly rebooting. It was fine earlier, but it keeps restarting and is unresponsive to any controls. It does not want to turn off either, so I have just locked the car with a CD playing at lowish volume.

sounds like you have a problem with one of the modules on the fibre optic circuit, no way to tell which without either doing a vcds scan or pulling some of the components and use a fibre optic link connector to bridge it

as youve had some issues with the nav , maybe try that one first

I had this happen some months back. I disconnected the battery in the end at a service station on the M4. I reconnected and all seemed well. I decided to remove an unofficial sat nav DVD as this wasn't working anymore and its not happend since . Might have been coincidence but no probs since I went back to my 2005 disc.

For what its worth, I just did a VCDS scan. its attached, loads of controllers cannot be contacted.

Just been out and disconnected the battery, after reconnecting it normal service has resumed. Not sure where to start looking, or what caused it in the first place.

Looks like some low voltages logged on freeze frames, I suspect during cranking the voltage is going down so much that controllers are crashing.

I think the low voltage ones are old, since I was unable to clear all the faults after I had a new battery fitted. The battery meter is still on 100%, and the fault occurred before I even started the engine to start the journey. It was odd because I had just sat in the drivers seat and the MMI screen popped up, even though I left the car with the MMI switched off.

It did not misbehave at all on the 200 mile drive back to Dorset from Cambridge, although I don't have the satnav disc in at the moment.

The only time I did these symptoms was when I spilled Turkish tea on the buttons. It would be unresponsive and keep rebooting.
I had to remove the MMI and flush it out with isopropanol from work.
Did you spill a drink or might someone else? What about someone cleaning inside - time to thrash the Butler again?

System is still behaving just fine. Last night whilst scanning the car and clearing faults from another battery disconnect (other reasons), I did the fibre optic test as well with the results that all is good.

onday,30,December,2013,20:18:38:10074
VCDS Version: Release 10.6.4
Data version: 20110418


Control Module Part Number: 4E0 910 468
Component and/or Version: Gateway H07 0070

Optical Bus Diagnostic : Standard

Controller Electrical Optical
19-CAN Gateway OK OK
07-Control Head(High/D3) OK OK
1E-Media Player 2 OK OK
77-Telephone OK OK
47-Sound System OK OK
56-Radio OK OK
57-TV Tuner OK OK
37-Navigation OK OK

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