Ok so I bought a used 2003 cooper s a couple weeks ago and it didn't have a radio in it. The dealership gave me 150 to go buy a new radio, so I purchased a pioneer DEH2100IB. I got the wiring harness the guy at best buy suggested (the 70-9003), the same one that crutchfield sends you.

However, upon tearing the car apart, I have found that the previous owner had an extensive audio/visual setup and now mine wont seem to work at all. I attached the wiring harness the way I'm supposed to, and the radio gets no power upon starting up.

In addition to the oem harness, there is a second white harness with 4 wires going into it. There are also 3 random wires in the dash, one yellow, one red, and one black.

I also found one red and one black wire behind the glovebox area, wrapped in electrical tape. These seem to lead to the back of the car where they are attached to nothing.

My gut is telling me to attach the red wire to the battery and ground the black wire, and just run off that as a power supply, but I don't know. What do you guys think? I will attach some pics.

Please help!

 

One more thing: the car has a rearview camera mounted and that is what the small black box in the rear hatch is attached to.

 

Question:

Is there a chance that my red wire just isnt connected to a working accessory-power wire?

Would the radio turn on without the accessory wire attached properly?

And, if it could be a problem with my 'red' wire, could I just splice the red wire into the yellow wire to see if my harness is working properly, and if so then I could find a different accessory wire to use?

 

I have absolutely no help or words of wisdom for you, sorry.

Just wanted to throw some sympathy your way, cause that looks like a freakin' nightmare.

One things for sure, it all made sense to someone at some point in time.

Good luck!

 

Ya thats a mess, I had my stock head unit crap out on me, or so i beleive that was the culprit, but when replacing it with a new on i feel like i went through a similiar problem, I had to wire my power into a fuse down in the driver footwell. I tried to get it into a fuse that would power on and off with the car but for some reason none of those would work, i ended up having to turn the radio on and off every time i got in the car. SO it sucked but u could end up having to do the same thing to get power to the headunit. I dunno why its so difficult it should be jsut a plug and play but of course bmw electricals ar enever that simple, good luck hopefully some one can solve both of our problems because i ended up taking the radio out cuz it was so annoyingly set up, iv been radio less for about 4-5 months now, but the supercharger, intake, engine, and exhaust have been music to my ears, granted making that symphony uses more gas but


goodluck

 

Is there anything attached to the battery already? My guess is that the red/black wire went to an amp, and the previous owner took it off the battery so he could save his fuse.

I would probably do what you suggested and hook it up to the battery and ground and see what happens. If you have access to a multimeter, use that on the head unit's wiring harness instead of the head unit itself.

Failing that, just locate the ends of all the wires. Remember that the car may also have wiring coming from the steering column.

 

If the OEM wiring harness is intact and the harness adapter you bought is correct, your headunit should at least power up. I wonder if the previous owner pulled pins from the OEM connector and put them into the white connector. Do any of the wires in the white connector come from the OEM harness?

Look at this diagram and see what is missing from the OEM connector.

 

I finally figured it out. Turns out I was using a dead accessory wire, so I just got lazy and spliced my accessory wire into my 12v constant wire. Just means i need to remember to turn off my radio when I get out of the car.