Sam Rothrock

I have a 2016 Q5. I tried to upgrade my Nav system with CarPlay so I bought one of the add-on kits that gives a you a box and wiring harness to plug into the back of the head unit. It was working good but I kept tinkering with it and when I tried to get the Head unit back in it seemed obstructed probably from the extra room taken by the CarPlay box and wiring harness. My mistake was I started trying to force it a little and then:

- The MMI display went blank/black. It is not backlit at all. As if it gets no power.
- The MMI control buttons on the console (ie. Media, Navigation Menu, Radio, Back, etc..) do not backlight nor do they seem to operate
- The Head unit lights for Parking Assist, and Auto Off and Traction Control DO WORK and are backlit, This is separately wired and seems to just be attached to head unit but not an integral part.
- The DVD player will not accept a DVD
- The A/C and heat controls are lit and seem to be working fine.


The things I've tried are:

- Ive removed the CarPlay unit altogether but now the OEM is not responding so I assume I have damage something in the OEM equipment
- I've checked and replaced fuses on the passenger side and in the rear.
- I did a loop test on the unit behind the glove box and on the amplifier in the back. Those were the only modules I could find.
- I figured I must have fried the head unit so I purchased another one used off of Ebay but after plugging it in I got the same thing. - As a last resort I detached the battery cable to see if something would reset. It didn't.
- I am not a mechanic but I happen to have a Ross Tech VCDS so I ran a diagnostic. As expected I got errors but honestly I don't know what else to try. I will attach a report of the scan. I also did an optical scan and it said it could not communicate with radio of instrument cluster. Here is a link to the report:
- Ive disconnected and reconnected all wiring to the head unit and have inspected wires and pins and cannot find an issue

https://docs.google.com/document/d/1...it?usp=sharing

I just can't afford to spend a bunch to repair it right now (out of work for now) so I would really appreciate any help for something I could try. About to hit the road for a road trip anniversary with the wife and its gonna stink to not have a radio.

Thanks in Advance!

Sam

ColoradoMark

Could you have knocked a wire loose behind the unit when you forced it? Odd that both your unit and the replacement will not work.

As a side note, my MMI is working intermittently. I talked to the dealer and they think I need to bring it in for an update. When mine doesn't work it will not even rise up or work with the backup camera.