HELP A Poor Newbie - Wiring new head unit

[DanielPhelps]

Hi all,
I would be SO GRATEFUL for any help you can offer me. I'm pulling my hair out trying to get my new Veyron head unit all wired in and working, but now that I've spent this many hours working at it, I don't want to just give in and pay someone to do it for me!

I've got three problems:
The first (and biggest) issue, is that, having installed everything that I can see, the head unit still isn't getting any power. EVERYTHING is plugged in, except this random yellow wire (please see picture).


I've had a look online and some people have mentioned that after market units sometimes need separately wiring into an 'always on' power supply. However, most people seem to advise doing this to the fuse box and this wire looks too short to reach all the way over there? Am I missing something? Also, even if that yellow wire does need wiring in, shouldn't the unit be able to run when the the car has been started if everything else is plugged in? I just have no idea what to try and am worried to just start attaching the wire to things for fear of wrecking something. Probably myself.
Second issue is that the person who sold me the unit on ebay has very kindly sent it without the correct screws to attach it to the dash! I assumed the unit would simply use some of the screws that came out of my old BMW Professional stereo, but none of them fit. Can anyone offer a helpful suggestion here?

Third issue is that I have two mystery wires, which I don't know what to do with, although they seem unimportant. Please see the pictures. Any suggestions?
Preview attachment 20170115_122659.jpg




20170115_122659.jpg
4 MB





Preview attachment 20170115_193728.jpg




20170115_193728.jpg
4 MB







Thank you for taking the time to read all this. I really would be very very grateful for any help!

[DennisCooper]

Hi,

None of your links or pictures work so harder to help you. Also, the audio head unit from a Veyron is incompatible with a BMW. However, is there a chance that this 'Veyron' unit is a cheap chinese clone type unit available from various ebay sellers usually based in the far east somewhere? if that is the case, then get the wiring diagram for the head unit to be 100% sure as to what it's for. 'Usually' on high quality head unit's it's for a 'switched 12V' supply and needs to be connected for the unit to power up. Until you are 100% sure that's what the wire on your head unit is, don't connect it up. If it is that, then extend the wire if required. Various sized screws are available from hardware stores.

Another possibility is that if it is indeed some cheap chinese replacement type unit from somewhere in the far east, it's faulty. Once you find out what the yellow wire is 100%, and connect it correctly and the unit still doesn't work, then get your money back and purchase a high quality brand unit and have that fitted.

Lastly, whenever I do see posts similar to yours where it's evident there's little or no experience with 12V electrics, I STRONGLY suggest you pay a reputable local car electrician to fit the unit for you both correctly and most importantly, SAFELY.

Cheers, Dennis!