91 Suburban, under dash lights stay on but the dome lights do not come on.

[ballencd]

Have not moved my Burb in the drive for about 10 days and when I went back to start it the battery was dead....like totally dead. 0VDC with a meter. I pulled it and put on a charger for a few minutes and the charger stopped and displayed "BAD BAT". Next step was replace the battery......for $180! Wow have they gone up. The car starts now and puts out 14.4 VDC while charging but under dash light stays on with all the door shut and the headlight switch turned off....(under dash part of the switch). The dome lights don't come on at all now but did work before this happened. IF I open a door the intensity of the under dash lights brighten some. The dome lights never come on now.
Have looked in the forums and can't find anything related. Anyone know where I should start looking. I would suspect a shorted wire somewhere but why are the dome lights out??? I guess I should start making sure that they are not burned out first making it two issues. Any other ideas?

[kwmech]

Start by checking the white ground wires going through the A pillar to the door switches for abrasion. OR just push the switch in manually and lightly pull, tug or wiggle the wires

[ballencd]

Fixed....I think, but not sure if what I think it was is possible??????

I inspected all pillar switches and cleaned while they were out with a wire brush. I also pulled the light fixture under the dash and both ceiling fixtures while I was at it. The rear ceiling fixture was a replacement by PO and was wired differently than factory but it has been working that way for several years so I am not going to look there for the problem at this time.

By the time I got all the switches back in place and had inspected everything..... the under dash lights had started working again with the door switches but the ceiling lights were still not working.......strange.....???

I found the horn fuse (also powers the ceiling lights) blown, no power to the ceiling lights but the under dash light uses a different power supply and it still had power.

I found a metal ring in the cigarette lighter hole behind the USB charging adapter that looked like it came off some other plug that had been in the hole prior to this point and not noticed. I removed the ring and replaced the fuse and everything works as designed so far.

I suspect that the metal ring blew the fuse (horn/ceiling light) and then back supplied the under dash light with a ground that made it stay on all the time taking out my battery. I'm not sure if that's what actually happened or if it could but I think it did. I do not have schematics that I can trace back and verify.

What do you guys think? Could this happen?

Inquiring Minds Want to Know...????:

[ballencd]

Anybody have the correct schematics for a 91 Suburban so I can verify my suspicions?

[ballencd]

No one has wiring diagrams of the interior lighting circuits and cigarette lighter circuits....? Anyone know where I can find one. I'd like to verify my theory. Thanks

[Corts60]

Member Hatzie has all the manuals you need. Look him up on the site.

[ballencd]

I'll look him up. Thanks