Best Buy had a good deal going for a pioneer head unit and a set of 6.5" speakers for $69, and having no radio OR speakers in my 'Manche, I quickly grabbed one.
The two wiring harnesses tucked behind the busted up tape deck corresponded to a wiring diagram I also found behind the tape deck, so I snipped and crimped away and wired up the Pioneer adapter.
Plugged the deck in and turned the key to "on", and nothing.
Unplugged the head unit, checked the fuse, it was fine.
Used a voltmeter to test the ground wire, the battery (memory) wire, and the Power/Acc wire, everything is perfect. 12.5v with the key "off" at the yellow battery wire, nothing at the "acc" wire. Turn the key on and 12.5v at the red "acc" wire, I used the ground wire to ground the voltmeter to so I know its a good ground, too.
Figuring the head unit was a dud, I exchanged it for a new one, plugged it in, same thing. Nothing.
Figured maybe the adapter was defective and one of the pins wasnt lined up right or something so I wired up the battery/acc/ground wires from the new harness, tested them, everythings good, but still nothing when I plug it in.
This is frustrating! Any ideas?