Electrical MEGA Gremlins

[fngearhead]

I've been poking around in my roommate's '91 Legacy wagon for awhile. The vent fan doesn't run. The fan works when wired directly to the battery. I swapped HVAC controls... nothing. It also has no dash lights. When the headlights are turned on, the radio display dies. The sunroof and RF window sometimes work. Their problem seems linked, both work or both don't work. All fuses are good. The radio harness was chopped from a previous owner's attempt at stereo install. I spliced it back together, colors match. Factory radio works, but has above mentioned display issues. I've been staring at wiring diagrams, thinking something is pinched, but wondering if there is some sort of relation between these quirks. I've got the car for sale right now and would love to have it fully functional before it sells. I'm thinking I'll just direct wire a switch to make the fan run and leave the rest alone.

[Dynamic Entry]

good luck man, i'd like to be able to help you but.... my signature hasn't changed in a loooong time

[gijonas]

Grounds!! So often overlooked and so often the problem.Locate all grounds that you can and make them better.

[SLODRIVE]

+1 on checking grounds. A little chafing and corrosion can wreak havoc on the electrical system.

Oh, and "-1" on direct wiring the fan. That kind of "re-wiring" will only lower your resale value, because not only will the OEM wiring need repair, but someone will have to undo the added circuits. That plus anytime there's a switch added to run a factory part, it raises red flags with any tech who may inspect the car.

[magicmike]

When you say the radio harness was chopped was the factory plug still there? When you say you connected the wires back up color for color, are you reffering to the factory plug? I only say this because a common mistake made when connecting an aftermarket or attempting to in this case is using the illumination wire for a radio ground since the cars parking light circuit (illumination circuit) "rests" at ground. So when someone is testing the harness for a ground wire they find the illumination wire because the lights are off at the time as showing a ground and connect the radio ground to that. Everything works greast until you turn on the parking lights and it pops a fuse somewhere.

Have you checked the fuses under the hood as well?

[fngearhead]

Yup, checked every fuse I could find. All are good now. The factory radio plugs were clipped off but still in the car so I reattached the wires color for color. The radio plays fine, but the display doesn't stay on. I get a split second glimpse of the radio station when the unit powers up. If unit is off, display works fine, ie- clock is on.
She's a beater so I'm not too concerned about resale. I'm selling for $800. I've checked a few grounds, but honestly don't have time for anything lately.