[Sully2603]

Hi there newbie poster here.
I have an Audi A5 (Obviously).
Ibis white 3.0tdi quattro convertible s line.
I am having problems with my mmi system.
I have sent both my b&o sound amp and radio amp away for repair.
It's the optic loop version.
They both came back with no problems on them according to Bose repairs Edinburgh.
So refitting both items back in car
Still mmi not working just flashes the welcome screen then goes off.
I have done the optic loop bypass and the tuner is the unit at fault.
Not possible (see above.).
Now I have checked fuses they are fine but the main harness that fits it the back of the radio tuner module has only 3 wires 1 brown,1 red,1,green and white.
Is that right or am I missing something?

 

[DrGER]

@Sully2603 : Can you get a proper VAG OBD scan of the car, in particular, Addresses 56 (Radio) and 5F (Information Electr.) using VCDS (or equivalent) ? Also, what is model year of your A5 ? Check the PR sticker in boot for the the PR code(s) for your MMI/Radio configuration.

In the B8 A4 platform, the MMI radio tuner is part of the optical loop; connections include the fiber optic cables connector, a single T8m connector with 3 wires (as you note, above), and two Fakra coax antenna cables:

--g

 

[Sully2603]

Sorry for sounding dumb But wtf? Lol I get the obd scan. But the rest is double Dutch?
So as I have read it correctly if I'm wrong the main harness has only 3 wires coming out of it?. There is a coaxial type cable aswell as an optic loop plugging the tuner.
And thanks for the tip on the sticker in boot to identify the setup of the mmi system.
I have contacted Bose repairs in Edinburgh to ask about a possible c/p on said tuner? But been advised that there is not?

 

[DrGER]

So as I have read it correctly if I'm wrong the main harness has only 3 wires coming out of it?. There is a coaxial type cable as well as an optic loop plugging the tuner.

If you have an MMI High system (not MMI Plus), that is correct; the radio sends a digital signal to the the MMI main unit through the optical loop. The wiring is for power, ground, and the diagnostic signal. Without a proper VAG-aware OBD scan with a (non-generic) tool like ODIS, VCDS, or OBDeleven, you're just guessing what might be wrong here.
Re the PR codes in your build configuration, a number of web tools can decode them; I like this one: http://vag-codes.info/ --g

 

[Sully2603]

This is the boot sticker I believe you asked for. Hope this helps.

 

[DrGER]

Looks like PR-7T6 (Navigation system (MID)), suggesting 3G+? Missing some PR codes hidden under the tear in the lower left corner of your image. Looking for a radio code starting with '8'. What model year is this A5 ? --g

 

[Sully2603]

2009.

 

[DrGER]

So, you're one of the lucky owners who has the vechicle data label affixed to the maintenance booklet (our NA model doesn't). None of the PR codes here points to which digital radio is installed in your car. PR-7T6 tells us you (should) have MMI 3G High; you can confirm by getting the MMI software version: [MENU] > MMI Setup > Version information (3G High starts with "HNav"). Unfortunately, not all build options are on the label. Your dealer should be able to supply you with the build PR code list given the VIN (at least AoA does it over here). --g

 

[Sully2603]

Yes I can confirm it does indeed have those exact letters on the screen when I scroll through the mmi screen and select version.

 

[DrGER]

Does your MMI 3G High system start & run with the digital tuner by-passed out of the fiber optic loop ? Thinking you need to get a proper ODIS/VCDS scan of all modules (though that might be difficult if the MMI main unit is at fault, say, due to failed hard disk drive). Right now, everything is guess work without known fault codes. --g

 

[Sully2603]

Definitely 3g high version.
And when I placed optic loop on radio tuner all mmi systems work as normal except radio although it does still show radio stations on mmi screen but doesn't tune them in nor no sound comes from radio stations.
But everything else works.

 

[DrGER]

You did hint at this in your first post, though it's good to confirm. Try to get a proper VAG scan with the radio out of the optical loop (but connected otherwise). My guess is you need to replace the digital radio module, regardless of what your repair shop says. Depending on the VAG part number, you should find plenty of these on the used market or from auto parts recyclers. --g

 

[Sully2603]

Yes I have come to that conclusion.
But now my only concern is finding one with the same part number.
I have seen 2 on fleabay but the last digit on the part number don't match up.
They are also c/p free.

 

[DrGER]

What is the VAG part number of the digital radio module ? Depending on the part number, alternates might be used based on production period. See item 1 here, for example: individual parts Audi A5/S5 Cabriolet (A5CA) 2010 year Audi EUROPA 35040 --g