Some assistance with MMI required

[conorc1983]

Hi all!! Thanks so much for the acceptance to the forum. I'm wondering could I ask for some sage advice. I picked up a D3 Audi A8 for an absolute steal (knowing it had some issues.)

I'm in the process of sorting out the DPF and some of the other engine errors but I'm having some challenges with the MMI system.

When I turn on the car, the MMI screen doesn't pop up and the buttons for "Media, Nav, Phone" etc near the gear selector doesn't turn on. I believe I've checked the fuses and replaced a few that were questionable - but still no success with the MMI.

When I ran the VCDS scan, it shows the following

Any assistance would be greatly appreciated!

 

[NHN]

That's allot of errors, I'd work through each one by one as allot going on there.

 

[JohnS3]

A lot of open circuit errors. I’d clear all the codes and work with the errors that return. CP is active on your climate control. Did you replace it?

 

[conorc1983]

A lot of open circuit errors. I’d clear all the codes and work with the errors that return. CP is active on your climate control. Did you replace it?

It may have been replaced before i purchased the car John. I'll work on clearing these tonight and seeing what happens. Ive also bought a few MOST loop bypass connectors and awaiting delivery.

From what i can see, theres a module in the boot / trunk, then theres a CD changer in the glove box and a satnav / SD card module in the glove box also. Is there any guidance as to whether these are the only ones that i need to be concentrating on?

 

[conorc1983]

So the plot thickens somewhat. I’m still waiting on the loop cables. But I thought I’d check power and cabling at the back of the units inside the glovebox. I found the following installed. There look to be too many pins in the back of this unit vs the connector so maybe someone just chanced putting it in? Does anyone have a model number of the one that I’m meant to have by any chance?

 

[s8craig]

Having too many pins just means you dont have all the options that this has installed, the fact that it was out of an A6 and you have an A8 would raise questions. Has it been coded up and component protection removed?

 

[s8craig]

This is your main issue for the MMI, the optical bus is open suggesting a break in the loop, each option in the MMI has a fiber connector with in and out sockets. So you need to find the radio and amp modules in the left of the boot on the D3 facelift and make sure they are connected and powered up. Maybe buy an optical loop so you can disconnect each module and bypass it with a loop to assist with testing.

1 Fault Found:
00384 - Optical Databus
011 - Open Circuit
Freeze Frame:
Fault Status: 01101011
Fault Priority: 5
Fault Frequency: 1
Reset counter: 232
Mileage: 213830 km
Time Indication: 0
Date: 2024.01.02
Time: 00:08:41

 

[NHN]

This is your main issue for the MMI, the optical bus is open suggesting a break in the loop, each option in the MMI has a fiber connector with in and out sockets. So you need to find the radio and amp modules in the left of the boot on the D3 facelift and make sure they are connected and powered up. Maybe buy an optical loop so you can disconnect each module and bypass it with a loop to assist with testing.

1 Fault Found:
00384 - Optical Databus
011 - Open Circuit
Freeze Frame:
Fault Status: 01101011
Fault Priority: 5
Fault Frequency: 1
Reset counter: 232
Mileage: 213830 km
Time Indication: 0
Date: 2024.01.02
Time: 00:08:41

Jesus Craig where you been hiding, haven't seen you on here for ages, maybe it's me