- Tue Jul 27, 2010 4:16 pm
#206442
Could also be a bad deck. Occasionally they're bad right out of the box.
The fact that the alternator and battery were recently replaced by the previous owner does not rule them out. It makes them MORE suspect. Cheaply rebuilt alternators often have bad regulators on them. On occasion, I've had to exchange Autozone alternators several times to get one that was good. And guess what, the parts guy put my bad one right back on the shelf! Now I go to the junkyard.
Also, a brand new battery if allowed to go flat just once, will lose HALF of it's ability to filter your alternators noisy charge (and it cuts it's lifespan in half).
Maybe the previous owner replaced a good battery and the new one went dead. Then replaced the alternator and recharged the battery.
Car stereos have a constant 12v memory connection and an accessory 12v connection that turns them on when the key is on. The constant is the white/blue on the car side which is yellow aftermarket on the adapter harness side. IF YOU ARE GOING TO RUN A NEW WIRE, MAKE SURE THAT YOU USE A GROMMET TO PASS THROUGH THE FIREWALL PROPERLY and of course to fuse the wire near the battery as previously mentioned. You can connect it to the ring terminal in the under dash fuse box where the alternator and starter are connected. You could run it to the under dash fuse box output, but this would be rather pointless since that is where the wire you are replacing runs to. Also, most of those option outputs are tied into other circuits.