• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

OEM Head Unit Wiring

blackmoose

New member
So, I'm trying to put the OEM head unit back in for unimportant reasons. On the wiring harness there are three dark green wires, two dark blue, and two yellow. Now yes I've looked at the Wire Diagram, but it only shows one dark green, one dark blue, but both yellows. I'm wondering if there's anyway to figure out which one goes where without pulling the trial and error process. Seeing as how one yellow is a power wire, I'm not trying to try anything risky quite yet. And my voltage meter isn't giving me an accurate reading. There are sixteen wires on both ends, and I'm trying to figure out if any of the duplicates have to be specifically correct?

Please help ):
 


since it sounds like you cut you plug off and threw it out, lol go to any audio shop and ask for the plug, ( for your year make and model) it will come with a 12 inch pig tail and the wires should all match color and size wise, they run 20 to 30 bucks.
 
It's a 98 SE, No, I have the wiring harness, when my sister's boyfriend put a aftermarket head unit in for a subwoofer system he cut the wires, but not like there'd be any other way to do it? All the wires match up, 16 wires on both ends, it's just there are duplicates and I'm trying to figure out which one goes where. Since the wiring diagram only mentions one dark green and one dark blue, I'm quite confused. Would a picture of the wiring help?
 
they should say or have a stripe of different colors.

in the future tell your sisters boyfriend to buy a plug with a harness that plugs into the factory plug. the new plug looks like the socket in the back of the radio. no more f ing up the factory wires.

this can be done for any car when swapping head units. its worth it if your re using the factory speaker wires all by its self. then putting the stock radio is real easy.
 


It is the stock wiring harness actually, we held onto everything that came with the original head unit including both plugs that go into it in case this ever happened, the only mistake we made was not marking them. the green and blues are the exact same color, and the two yellows are obviously the same color cause the wire diagram that is used for this car uses the yellows twice. But, that wire diagram is generally for after market head units, no? I'm going to attach a picture of the wiring. I have them all wired up, for safety purposes, I haven't tried powering it up yet cause I don't want a electrical fire because of the yellow being a 12V+.
IMG017.jpg
 
Last edited:
after you get it plugged in for a test, and it works, do your sister a huge solid, and solder the wires back together, and use shrink wrap on the splice, it will last for ever that way.

the twist and tape set ups never last long.


heres a vid if you never did soldering, its so easy. you can get a soldering iron for about 10 bucks, the heat shrink wrap cost about 5 for a box of tubes, and 3 bucks for the flux core solder. all found at radio shack.

ff to the last 1/3 of the vid unless you want hear this guy just talk a lot lol
 
It is the stock wiring harness actually, we held onto everything that came with the original head unit including both plugs that go into it in case this ever happened, the only mistake we made was not marking them. the green and blues are the exact same color, and the two yellows are obviously the same color cause the wire diagram that is used for this car uses the yellows twice. But, that wire diagram is generally for after market head units, no? I'm going to attach a picture of the wiring. I have them all wired up, for safety purposes, I haven't tried powering it up yet cause I don't want a electrical fire because of the yellow being a 12V+.
IMG017.jpg

No way that's stock, I can't imagine why it wouldn't be, but I just want to see that's some sort of rewire. Those wires are too clean and none of them have any marks on them. I also have a 98, as does my friend, and I've put radios in a variety a GP and none of them looked like that.
As I recall, your colors should be orange for the constant "trickle" 12v
yellow for the switch 12v power wire
brown for the illumination
gray for the dimmer
tan and gray for front left +/- respectively
light and dark green for front right +/- respectively
brown and yellow for rear left +/- respectively
dark and light blue for rear right +/- respectively

as an SE you MIGHT have an antenna too in which case you'll have a pink wire.

Some of the slots in the harness should be empty.

For future reference, any time you meet someone that's cut stock radio wires, slap them upside the ****ing head as hard as you can.

edit: here's the diagram from the12volt.com, appears i'm correct on that, 1998 Pontiac Grand Prix Stereo Wiring Information

either GM made a joke with your car, or someone rewired it.

edit2: for the power wires, just usage a voltage meter to test them, car off one should be constantly powered, the other should receive power with key-on, the speakers mixing them up shouldnt be a big deal, but you can easily do guess-and-check with those.
 
Back
Top