All you have to do is replace that little red capacitor on that lower circuit card.....
Just kidding.
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Yes, it's a damn frustrating thing to deal with. Impossible to see, impossible to feel without getting your fingers cut to pieces. The cooling fins on the back are razor sharp. Awful. Mine didn't work but I somehow got it working when I removed it when rebuilding the IP and AC systems. When I had it out I could fiddle with it, and with a speaker hooked up (mandatory, otherwise it will fry the amp internals) I got a little scratchy noise and the hunt was on. I got good power and ground, cleaned the pushbutton contactors with a pencil eraser, ran clip leads to the green and black speaker wiring....and got lucky, mostly.
There is no inline fuse. Juice comes in the red wire, and it's chassis grounded. But you probably know that. So find that red wire into the harness and see if you have juice there.
In this pic you can see that red wire at the right rear. That's also where the antenna generally cable goes.
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And here's something odd that I discovered. You know that goofy "other high-beam" switch on the floor, the one that changes stations? When I plugged in THAT strange, silvery cable (left side of radio) and hit the floor switch, the radio went silent. Pulled that cable out and my "repaired" radio worked again. Then I bought new rear speakers for my non-stereo AM/FM, along with the functioning front speaker and fader control (which I also took apart and cleaned the "wheel" with pencil eraser) I have
70's sound!
I can't add much else, and I commiserate with your situation. Removing and tinkering is a total *****. Get a skilled teenager to do it!
Here's the dead single rear speaker that my non-stereo car came with. It's gone, and simple, low-wattage coaxials went in its place. Hard to imagine there was factory monaural FM back then. But the FM Multiplex option was a big upgrade!
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Lots of work, completed!
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