View Full Version : Help with Aftermarket Headunit Install w/ Bose

11-14-2012, 07:19 PM
I just picked up a Pioneer DEH-X5500HD headunit to replace my stock one. I've been looking at the wiring connections so I know what I'm doing when I install it this weekend and I have a couple questions. I tried a search and found a decent amount of threads but couldn't find an answer to my questions.

1. The harness I have that has the RCA connections also has a single Blue/White wire in the harness that reads "Amp Turn On"

2. The harness that came with the headunit also has a Blue/White wire with a tag on the wire reading "System Remote Control" In the manual for the headunit it says to "connect to system control terminal of the power amp or auto-antenna relay control terminal"

3. The antenna adapter I have also has a Blue wire with a metal connection at the end and a tag that says "12V DC". Instructions say "The Blue wire must be connected to the power antenna wire of the new receiver. The receiver power antenna will typically be Blue or Blue/White."

4. There is another harness that also have a Blue wire that is for the "Power Antenna".

Here's pictures of everything I'm talking about.

1. RCA Harness
http://img708.imageshack.us/img708/8397/number1al.jpg (http://imageshack.us/photo/my-images/708/number1al.jpg/)

2. New Headunit Harness
http://img109.imageshack.us/img109/1302/number2u.jpg (http://imageshack.us/photo/my-images/109/number2u.jpg/)

3. Antenna Adapter
http://img255.imageshack.us/img255/3645/number3.jpg (http://imageshack.us/photo/my-images/255/number3.jpg/)

4. Power/Speaker Harness
http://img440.imageshack.us/img440/7660/number4p.jpg (http://imageshack.us/photo/my-images/440/number4p.jpg/)

If I had to guess I would connect 1-2 and 3-4. But then I look at the wording for 3 and it says "of the new receiver" which would be number 2. This is where I'm getting confused. Which wires should I be connecting together? Thanks to anyone who can help me out.[hail]

11-14-2012, 08:53 PM
#1 is an input. The amp in the back of the car needs 12V+ trigger to turn on. You need to apply 12V+ to that wire to getcha some tunes.
#3 is an input. The add-on amplifier device you have there needs 12V+ to do it's magic. You need to apply 12V+ to that wire to getcha some reception.
#4 is (again) an input, but I don't think it is actually present or necessary to connect. The meaning of that wire is to send 12V+ to the car's factory antenna amplifier. I do believe in the A4's that all the antenna amplification is done within the factory radio. This is why you have to use an add-on antenna amplifier (photo #3) when you remove the factory radio. I would advise that you leave #4 disconnected unless you have some sort of problem with reception.

#2 is your 1-and-only OUTPUT. That is the 12V+ signal from your aftermarket deck. It goes hot whenever the unit is turned on, powering up your bose amp trigger line and antenna amp.

I would connect #2 to BOTH #1 and #3.

11-14-2012, 11:02 PM
Dude if I tried to help the car would end up selecting reverse when you put it in first after wiring it up, don't ask me how but it would happen.
Im also thinking of doing a diff head unit soon but ill let a audio place do it for me.

11-15-2012, 04:31 PM
I installed a deck in my old car (an intrepid) and it was a piece of cake. The Audi, not so much

I do have 2 last questions.

For the antenna adapter (#3) the blue wire has a metal connector at the end, almost looks like it should be connecting to one of the plastic harness connectors. Should I just cut that off, strip the end, and connect it just like all the other wires?

There is a wire with a brown connector that hooks onto a tab on the back of the stock radio. It looks like a ground to me. The new harnesses also have a ground wire. Should I just ignore the stock brown wire?

11-15-2012, 07:25 PM
A - That connector isn't for snapping into the Audi adapter. It is a barrel connector. Often the aftermarket head units will come with the "remote" or "power antenna" wire that has barrel connector pre-installed. That does not appear to be the case for you, so you should cut it off and splice the 3 wires together as discussed above.

B - Yeah, that's a ground. You can just ignore that.

11-16-2012, 05:08 AM
You're the man walky

11-17-2012, 05:04 PM
Word of advice to anyone coming across my thread in a search, look into buying someGround Loop Noise Isolators (http://www.crutchfield.com/p_127SNI1/PAC-SNI-1.html). I was getting a loud pop noise coming from my speakers when I changed stations or input sources as well as when I turned the car on/off. I called Crutchfield and they told me it's a known problem with some Bose amps and they sent me out 2 sets for free. Hopefully they take care of the problem