92 Regal, no power to radio.

[Robbie]

So I've done an aftermarket swap on this one before, using a plug-in harness, going through the factory amp. I've removed it once or twice and reinstalled factory setup with no issues.

Since then, I've had the original ECU replaced, and the key chime is always active, even without key. The dashboard lights also rarely work.

 

Also, I suddenly found no power anymore to radio, be it factory or aftermarket. I've got nothing. I wired it temp to cig lighter, but this is obvs a super sketchy temp solution.

 

What would cause this circuit to die? All fuses are ok. Before I tear stuff apart, maybe someone has an idea of where to look first?

[GTP091]

I’d  dig out the ohm/voltmeter and start testing the grounds first. Test for 12v at the harness just to be sure you don’t have an open circuit.  My bet is you have a bad ground.

the instrument cluster might need the ole resolder trick to get it working. Especially if it seems to work based on temperature or humidity.  You could also have corroded contacts.  Would need to pull it to check.

Do you have a set of OEM manuals?

[Robbie]

Thank you, GTP!

A grounding issue, or some kind of bad contact would make a lot of sense, now that you mention it. This also reminds me that my dad once fiddled around the washer reservoir area while trying to replace a cracked hose down there; he ended up disconnecting a bunch of wiring around that fuse box for better access, and failed to properly reconnect everything. I had to break my head over a starter-cranking-no-spark situation... (He meant well, but he's quite old and forgetful. It's a little funny in hindsight )

I have no manuals. All I've managed to find is a blurry, general PDF electrical schematic, and without any wire coloring info. So I'm pretty-much going in blind with a tester and a prayer.

Are there any better free resources?

If I shell out some money on an actual manual, which one would be the best/most accurate for a 3800TPI Regal?

[GTP091]

I don’t know of a good free spot to get a manual.  You’d really want to get the OEM service manual for your specific year. They’re cheap on eBay.  it’ll have wiring diagrams and troubleshooting for lots of electrical issues. Also everything els you’d need later on.
search : Original 1992 Buick Regal Shop Service Manual Genuine GM.

looks to be one on there now for 13usd.

Your voltmeter is your friend here. Use ohm selection to look for ground and 12v for power.  If it’s, not that your deck should have a fuse on the back of it.  You could also just do a bench test on it to quickly rule out the head unit if you have a 12v source. I bet your dads ‘fixin’ is part or all of the issue.  It’s likely an open circuit somewhere and sounds,like though have em for sure.

[GTP091]

This might help… but doesn’t list anything for factory amp… 

https://www.carstereoremoval.com/htm/WireCodesBuick.htm

https://www.the12volt.com/installbay/stereodetail/360.html

Edited March 24, 2023 by GTP091