Oh. You didn't mention the adapter harness. The problem comes from people who splice the new radio's harness into the car's harness without using a wiring adapter. I never looked at those adapters so I don't know how they handle the ground. The original radio had a braided strap bolted to the radio's case. Later in the '90s they went to a light black wire that was clipped to a terminal on the back of the radio. If you don't use that ground wire, your new radio will be grounded through the outer shield of the antenna cable. That shield is very effective at keeping out interference but it makes a very poor power ground for the radio. Use the original ground wire for your new radio.
There should be two places to look for fuses if I remember correctly. My Dynasty is a '93; there are some differences between the two model years, but most of the electrical wiring is the same. The fuses inside are behind a removable plastic cover inside the glove box. By '93 there was a second fuse box near the battery. I think your '91 has that too.
If you look closely at the fuses, you'll see they have two tiny holes on top. Use a test light with a sharp point to touch those points on each fuse. Turn the head light switch on so there will be voltage to the running light fuse, then test both terminals of every fuse. You're looking for one that has voltage on one terminal but not its other one. That's the fastest way to find a blown fuse.
Wednesday, June 2nd, 2010 AT 3:57 AM