MMI starts and then turns off

[john81]

hi, i’ve got an a4 avant 58plate 2.0tdi . recently mmi stopped working. i press any button on centre console , screen logo comes on and few seconds goes off. i been reading here and brought the loop to test individual modules in the boot. no luck starting mmi. any help will be appreciated . thank in advance.
lights in buttons don’t work either.


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[Gunnark100]

Delete.

[john81]

https://uploads.tapatalk-cdn.com/20190325/1ce3292190f8d653e598e7d2373794ea.jpg


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[john81]

https://uploads.tapatalk-cdn.com/20190325/427168480e9bca6085bcb360ec2e5785.jpg


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[john81]

Delete.

Hi Gunmark,
i’m not sure which one exactly but that’s the photos i took this morning.
my bluetooth stopped working just before i think , the audi emissions update. there was some wet spots in drivers carped and spare wheel compartment last year due to a blocked sun roof pipe.


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[Gunnark100]

Hi Gunmark,
i’m not sure which one exactly but that’s the photos i took this morning.
my bluetooth stopped working just before i think , the audi emissions update. there was some wet spots in drivers carped and spare wheel compartment last year due to a blocked sun roof pipe.


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If all modules(bt,amp,cd,radio,nav) are "properly" tested with loop and all fuses are ok(modules receive power)...then it "must" be headunit behind glovebox.

[john81]

this one? i went with the loop to test but screen did same behaviour . all apart the one on this photo I saw the fibre red light blinking from units. the one on this photo I didn't look if blinking or nothttps://uploads.tapatalk-cdn.com/20190325/e2d2f3c329bacf06ba847f1490c0e466.jpg

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[Gunnark100]

this one? i went with the loop to test but screen did same behaviour . all apart the one on this photo I saw the fibre red light blinking from units. the one on this photo I didn't look if blinking or nothttps://uploads.tapatalk-cdn.com/20190325/e2d2f3c329bacf06ba847f1490c0e466.jpg

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No, this is gateway, headunit is next to the blower, so to say straight behind glovebox...but you cant test those with loop(mmi will not wake up if those are isolated).

[Gunnark100]

wait i will double check, maybe on b8 it was behind climatronic.

Update:
You need to remove:



air conditioner operating unit





CD changer -R41- from dash panel




air conditioner operating unit

[john81]

reading around someone mentioned under carpet

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[Gunnark100]

reading around someone mentioned under carpet

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Updated my previous post. How you tested bt,radio,amp,cd with loop?

[john81]

I removed the fiber connector from each unit one at a time and plugged the loop connector to the car loom

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[Gunnark100]

I removed the fiber connector from each unit one at a time and plugged the loop connector to the car loom

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did you restarted car also after each isolation? Headunit link i sent to your pm box!

[john81]

did you restarted car also after each isolation? Headunit link i sent to your pm box!no

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[Gunnark100]

no

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Ok, busy evening for you. Keep us posted, test all modules again(bt,nav,radio,amp,cd) and after each isolation ignition off on, or so to say ignition "on" at least ones!

[Gunnark100]

Probled solved or....?:confused:

[john81]

Probled solved or....?:confused:

would like to thank you Gunnar for all the help in fixing this issue, it was the bt module fault as you suggested in your exhaustive diagnosis . thank you so much. i will get another module and replace. regards. john


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