Hopefully someone can help me with this problem that is driving me crazy. I have a 1990 V1500 Blazer. A while back I had a shop redo some of the wiring since all the accessories wasn't working correctly. Not too long ago my electric rear window stopped going up and down. I pulled the panel off the tailgate and the small wire harness that goes from the window motor to the cutout switch was burnt at the terminal. I cut the small terminal off and wired it directly, bypassing the cutout switch. My window still doesn't work from the inside or outside. The motor doesn't even make a sound. My wife took the blazer to get a safety inspection and the horn all of a sudden stopped working. She got a new fuse andinstalled it and it worked for a little while and then blew again. I checked the wiring and they have the yellow wire from the horn contact spliced with the orange accessory power wire going into the fuse box power slot. That doesn't seem right to me. Everytime I try to put a new fuse in the horn/dim slot, it sparks and blows immediately [:@]. Also, my cigarette lighter doesn't work since that is where I plug my cell phone recharger in. Obviously I have a short somewhere but I have no idea where to start. I do notice that when I hit the rear window up/down switch on my dash, the overhead lights dim slightly until I release it. Sorry for being so long, but hopefully someone can lead me in the right direction. Thanks.

Billy

 

Wow, that's a lot to cover all at once.
For the horn, possible turn signal switch wiring rubbed through inside the steering column.
Maybe a bad rear window motor. When the interior lights dim it seems that power is going to the motor but it's drawing to much power.
I thought the cig lighter and the overhead light were on the same fuse...lighter housing short to ground?

I don't have the wiring diagram although I do need to get a manual for the '90.
To find shorts to ground I have used a headlight with jumper wires. One jumper from the power side of the headlight to one side of the fuse terminal, (fuse removed) and the other jumper wire from the other terminal of the headlight to the other fuse terminal in the fuse box. When the short is present the light will be turned on. Then start disconnecting wire connections to different components. When the headlight goes out, you've found the circuit that has the short.

I hope I didn't make this sound to complicated, if I did let us know and we'll try to simplify it.

 

Thanks for the help, I will definitely try that. What type of headlight are you using? I thought for the horn, the wire went into some type of horn housing. Does it seem right to basically be hotwired to the power terminal on the fuse box? Is there a way to check the rear window motor to see if it is still good or not? Thanks again for all the help.