MMI Dead, Screen Black, A8L D3

My Audi A8L MMI was dead, stuck at open, black screen, doesn’t close, every time I push a device button or reset the MMI, MMI initialize screen would come  on, and went black, while it was on, I could hear the relay clicking in the trunk under the back seat. 

VCDS scan would come up with: No communication with Head Unit, Optical Bus: open.

The culprit was the 5A yellow fuse was blown, I might have shorted the line somehow while working in the trunk. It did give me a great scare.

5A Fuse

fuse blown

9 Comments

  • I tried to turn on the hidden menu so I could activate the graphical display for the parking sensors. After I did this I reset the MMI, and now it won’t turn back on. The fuse you describe here is good and VCDS can’t communicate with the controller.

    Not sure where to from here, I disconnected the battery to see if it just needed a reset.

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