Radio Wiring/Wiring Harness Issue - Alpine Head Unit to Continental

MrBonus · 09-29-2016, 05:47 AM

I purchased a Continental Radio/USB MP3/WMA/Bluetooth 12 Volt (TR7412UB-OR) last week. One of my car's previous owners installed an aftermarket Alpine unit along with a speaker system.

Upon removing the Alpine, I realize that an adapter was not used to tie into the OEM harness and rather it was spliced in. A friend informed me that the Continental likely works off our factory harnesses. Does anyone know if this is correct?

Secondly, where can I acquire an original OEM harness to splice back in?

Thanks for any help you can give me. I know practically nothing of aftermarket stereos in cars.

aread · 09-29-2016, 05:51 AM

Subscribed. Looking at buying the same head unit to replace my Alpine.

Franks89-911 · Franks89-911's Garage

Ian,

Don't know if this will help you or not. I found this harness for a 964/993 from a company in Norway, and ordered it a few days ago. It says it fits in between the 911's factory harness from those 964/993 model years and directly into that Continental radio you're installing.

ISO harness Porsche 964/993

I've ordered one because I'm in the middle of an aftermarket radio install too (not Continental though). It doesn't look like this thing from Norway will actually fit my car's harness, but there is a method to my madness. I plan on disassembling the Porsche side of this Norway plastic harness, keeping the wires with the flat male plugs on that end intact. Then I will cut the Continental side harness off entirely and seeing if I can plug the male ends from the Porsche side directly into my factory female harness on my 911, and splice in the bare wires from the Continental side to the aftermarket radio's harness. See pic of my car's factory harness.

Maybe you could do the same thing. Speaker wires could be an issue for you though if your aftermarket Continental radio's harness integrates all wires like my aftermarket (Kenwood) does. I don't know.

I only have 3 wires left to connect from my aftermarket to my car: hot, ignition, and ground. All my speaker wires are connected. Hopefully, my solution will work. If not, I'm only out $16 and the shipping from Norway was free, fyi. Trying to avoid at all reasonable costs, cutting into any wires from my car, or soldering anything.

Anyway, good luck and keep us posted.

MrBonus · 09-29-2016, 07:01 AM

Thank you, Frank. I found that site as well and since my harness is already cut, I was going to contact that company and find out if their universal harness would work.

http://www.bergvillfx.com/index.php/products/car-audio/universal-iso-harness.html

Franks89-911 · Franks89-911's Garage

Quote:

Originally Posted by MrBonus

Thanks for any help you can give me. I know practically nothing of aftermarket stereos in cars.

These may also help you. These are diagrams of the radio wiring in 88-89 911's depending on the audio package you had with the car. My car as stated came with the preamp under the seat, so I used the one that depicted the preamp setup.

Franks89-911 · Franks89-911's Garage

You might also ask a gentleman named Stefan at SWStereo in NJ if he has an original factory harness he can sell you or if he can make one for you. Looks like about all they do is work on Euro car stereos. http://www.swstereo.com

MrBonus · 09-30-2016, 05:45 AM

Thank you for all the info, Frank!

BergvilleFX got back to me with the following as well, asking about the universal adapter:

It is difficult to answer your question, the fitting of this harness depends on your elcrrical skills and the existing wiring in your car. I would use this solution if I were to do this, it would be an easy thing to splice these cables init the wiring. If you have a crimp tool, I could recommend the unviersal connector with pins instead.

I'm also going to look into some sort of an adapter for the RCA jacks for the aftermarket speakers in my car.

MrBonus · 09:53 AM

For what it's worth, I took it to a local car audio shop for the install. I purchased this for them to cut into the modified harness:

https://www.amazon.com/gp/product/B005YENZYA/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1

And it ended up looking like this:

For the price, I'm very happy with the functionality and look. I decided to retain the internal microphone rather than mount the one that came with the unit.