No power to stereo-81 vette

[ladams]

I had the radio on my 81 working long enough to replace the speakers, the next day when I started it, the radio was not working. I checked the fuse, it was ok, and I checked the two power lines with a test light. The constant power wire is ok, the ignition power wire is showing nothing. Anyone have any ideas? It wasn't working when I bought the car but after I took the console apart to fix the power windows it started....for a while.
p.s. I'm very new so you'll have to spell it out for me.

Thanks

 

[SIXFOOTER]

Here is the power distribution drawing for the ignition switch
See the Yellow wire? That runs the radio and the pulse wipers. Is the Radio fuse hot when the key is on and off when the key is on?

 

[ladams]

I checked the fuse and it is not hot whether the key is on or off.

 

[SIXFOOTER]

OK, your going to need to look at the ignition switch. Its on top of the steering column, sounds like it may have some crud in it making it intermittent. I'll take a look at mine, give you a little more info

 

[jdp6000]

I had the radio on my 81 working long enough to replace the speakers, the next day when I started it, the radio was not working. I checked the fuse, it was ok, and I checked the two power lines with a test light. The constant power wire is ok, the ignition power wire is showing nothing. Anyone have any ideas? It wasn't working when I bought the car but after I took the console apart to fix the power windows it started....for a while.
p.s. I'm very new so you'll have to spell it out for me.

Thanks

Welcome neighbor! It is possible its the ground. But if you have tested the ignition power wire to ground and have nothing its not likely.

See the diagram above? Find the brown wire coming out of the ignition switch. Check it for power. It supplies power through the ignition switch to the fuse panel. If it has power the problem is on the otherside of the fuse panel. Check the yellow...which is the one I assumed you checked..

As you can see the yellow also powers the theft deterrent system. The module is under the console. This is what you may have rattled when you fixed the windows.

Note that the brown from the ignition also powers the wipers. Do your wipers work? If they do work its not likely a problem with the igntion switch or the brown. Replace the radio fuse anyway. It may look good but you never know. You can also check for power on either side of the fuse. Brown supplies to one side and the yellow runs out the other...theoretically. So if you have the ignition on and the one side of the fuse has power then there is no reason why the fuse would not connect the circuit and send power out on the yellow.

Lastly did bubba get a hold of the wires? My yellow was cut half way up under the dash and rerouted to the wiper....I found it when checking a similar problem. Make sure the wiring is right.

Jim

 

[ladams]

Success!!!!!!!!!

Thanks alot guys and/or girls, I checked the fuse again and found it was, indeed, good. However...when I pulled the fuse and checked each side, I found that one side was live and one side was dead. I have had a problem with very light corrosion on several contacts so what I did was took the fuse and "thickened" the tabs by putting a dab of solder on each side so it would fit tighter in the fuse box. It works fine now.
My first headscratcher solved!
Thanks again.