So I want to replace the ghetto blaster with an original OEM stereo for my '87 IROC restoration. I'm not an audiophile obviously. I was lucky to find the original wiring still in pretty good shape but a bit shorter than I would have liked. Had to splice in a new (aftermarket) pigtail(s).



I found this wiring diagram and it seems to be close but not quite right for an '87. The "lights on" grey wire and the brown "lights dimming" appear to be reversed. This results in there being no lights on the head unit, no FM reception and no memory until the head lights are on. The two 12 volt feeds, one from IGN and one continious are correct according to this diagram but still no memory when key and lights are off.

What am I not seeing or reading right?


Also looking for mounting brackets.... https://www.thirdgen.org/forums/inte...-mounting.html

 

My experience has been that gray is always 'lights' on GM products, even way back into the good ol' days. It sounds like you might have the continuous power and light wires reversed. Do you have a test light??? That would be the easiest way to test things. If you test the problem wires with a test light, you can test for proper operation without sarificing your radio. I think you may have to undo some of your wiring there and figure out which wires coming out of the car are the power, light, dim, etc and then feed them into the appropriate pins on your new plugs.

 

It was my same thought that those two were hooked up backwards. I switched them and it's pretty much the same.

Yeah, I tested every circuit with a volt meter. It's easy to pick up the illumination wire with the voltage variance as you dim/brighten the lights. The guy I got the unit from has given me a few ideas to test the unit before I send it back. ::shrug::

 

Guy who sold me the unit suggested removing the dimming & light's on power feeds. Did that. It worked fine for about 2 minutes then nothing. I've lost the 12V feed (yellow wire) from the ign switch. Would there be a fuseable link in that line? It doesn't go to the fuse box, the orange constant 12V feed does. Looks like I'll be tracing more wires than I had hoped to..... ::shrug::

While it was working I had the IPOD hooked up. It sounded pretty good for an old head unit and crapped out speakers (which will be replaced soon). How big a job is it to replace the dash speakers? Can it be done without taking off the dash pad?

 

Perhaps there are wiring issues deeper into the harness than just at the plugs. Not sure if there is a fuse on the IGN...a Haynes manual would be very helpful at this point in time, a GM manual even better. Changing the speakers requires removing the dash pad. Its only a bunch of screws on the bottom and the 6 or 8 on the topside. Not too bad.

 

I'm starting to think there's quite a few gremlins in the electrics in this car. Now it's the hatch pull down motor not working. Seems like you chase down one bug and another pops up. Remind me again why we like these cars? *lol*

 

based on what I can see, you have the orange wire from your new connector hooked up to the orange wire in the car. the Yellow wire on your new connector should be hooked up to the orange in the car, connect the brown wire in car to orange wire on connector.. and check the fuses again, there are two one for constant and one for accessories, which also runs your lighter, etc.

 

I'll give that a shot tomorrow. Thanks. Standby......

 

You nailed it 84ws689bird. The diagram is upside down. Oh wait, maybe that was me standing on my head trying to see what I'm doing!



Quick, somebody hand me the wire cutters!

Never ceases to amaze me how someone can hack up a wiring harness. Egads!!! What a mess. I'll post pics of the crap I pulled out of there today. At least the stereo works now.

 

glad that worked. looks like you have the wiring harness to an aftermarket alarm or keyless entry system there. and the speakers can be done in our cars in about an hour if your careful.

 

Yeah it was an alarm system. Definitely not a professional install and if it was I wanna meet the guy and give him a piece of my mind. What a hack job. You can see where they were searching for an orange hot wire from the ign, probably to the starter relay and they sliced open every orange wire no matter what color tracer was on it and did they seal them back up with tape? NO!!! Ijjits!!!

The yellow hot wire from the Ign switch to the head unit is dead. I can't trace beyond where it enters the harness. I ran a separate 12 volt line to the head unit from the acc spot on the fuse box. All I have to do is remember to turn off the deck when I'm finished with it.

This is some of the stuff I can't identify if it's OEM or not.





It's gonna take me a few more hours to straighten it all out. That black box in the upper left hand corner of the first pic has me worried a bit. I've already eliminated that relay on the right.

So I get the stereo working. Nothing from the left rear channel. Pop the sail panel off and pull the speaker out and someone's cut the speaker wires. ::shrug::

Having the seats out of the car certainly made it a lot easier!

 

the black box upper left is factory, you just have to clean it up and replace it up in the dash. the relay was in fact a starter kill relay, making it impossible to start the vehicle while the alarm is set. glad you yanked it, I hate 'em. third, any wires that go to that white harness from the alarm can be traced back and removed from the cars wires where they meet. looks like a fun time..

 

Thanks 84ws689bird. You've obviously spent a good amount of time under the dash of these things! I appreciate your help. Would ya like to come over for a beer sometime?

Anybody in Ontario (eastern end maybe) that might have a set of these mounting brackets?

 

http://www.installdr.com/Harnesses/GM-Wiring.pdf

I prefer this diagram to the one in your 1st post.

 

Thanks Reid. That's a lot better. Makes perfect sense when they illustrate the connectors from the end you typically look at them.

Anyhow, great bunch of guys here willing to help out. I appreciate it a lot.

 

Ive been there man.

One too many times.

 

Hey there!...happy belated "Canada" day..EH!!! Thank-You kindly, Just received the "moose killer" headlight grills. They'll look great after some gloss black paint. Just to set the record straight...I didn't ditch you on that wiring project,..I was being sarcastic when I said I was a "wiring genius",..I suck! at wiring. I've done my share, but I'm better at re-wiring the whole kit & capoodle rather than jumping into someone elses wiring nightmare & trying to diagnose up from ground wire...know what I mean?....anyways..again thanks. (p.s: I heard if you apply a thin layer of "Black Flag" to the light grills... the bugs will stay away until ya hit 50!) TGO guys aren't even laugh'in...they just want to know is that m.p.h. or k.p.h...EH???

 

Glad ya got 'em Dodgy. Or is it Chevyismo now? I knew you were pullin' my wire with the genius remark! It's near impossible to diagnose those things over the internet. Anyhow, problem's solved.



So other than the mini-jack in the face plate you'd never know this wasn't 100% OEM. I fabricated the mounting brackets myself in 10 mins. All buttoned up and sounds perdy good too!