Electrical Nightmare
 

Hi, my name is Michael and I live in Sacramento, CA.
I picked up a 91 S10 Blazer 4.3L TBI, 4x4 :icon_playing:to go play in. It was totally neglected and I knew I had a ton of work to do. I replaced the whole front suspender, and I'd bet my last pay check the shocks we the original from 91, same with the tune up. I've never seen spark plugs that bad:icon_doh:, but man that blazer ran like champ.
I'm no mechanic, but I'm not afraid to jump in and figure it out as I go along. When it came time to do the electrical work I noticed my head light switch was bad, a family member suggested a friend of her's that was going to school for this stuff:icon_no: he suggested a toggle switch:icon_doh:. So I got the book Haynes book and looked up the wiring for the headlights.
There are 4 wires running to that switch, (Red) the battery, (Yellow) that looks like it goes from the headlight switch to the dimmer switch, (Brown) for the turn and side marker lights, and (orange) for the cab lighting.
He came to the conclusion that (Red) would be the (Power), tie (Yellow and Brown) together for all the exterior lights as the (Acc) and the ground it. BAD IDEA!!! All three of those wires are hot:icon_hyper:
I never saw a ground wire light off like that, it looked like the fuse off a stick of dynamite. It ran through the whole system, cooked all my wiring.:icon_shrug:
I picked up an electrical book and I figured out the headlight/dimmer switch, but I have a mess on my hands. The book isn't very help on the wiring to and from the (PCM)
I'm having some trouble figuring out the pin lay out.
I would love to start putting this back together.:icon_playing:

Thanks,
Michael.

*Moving to 1st Gen Tech* - The new member area is for new member introductions. If you would like to create a new introduction thread, please do so in that section.

I never understand why someone would suggest putting in a toggle switch to control the headlights when the headlight switch is pretty cheap to begin with... Sounds like you have fried the wiring pretty good. You will have to repair/replace all of the burnt wires at this point.

As far as wiring diagrams/pinouts go, the aftermarket manuals SUCK. Have a look on eBay for a set of factory manuals. They cost more, but they are priceless when it comes to the information that is between the covers.

Here are a few current auctions:
1991 91 Chevrolet S10 Truck Blazer Electrical manual - $25 buy it now + $6 s&h
1991 91 S 10 S10 Truck Service Repair Manual F/Shipping - $27 buy it now + free shipping

Thanks for the info.

Sorry about posting in the wrong place, first day on the job.

Michael

No problem, that's why we have the 'move thread' option! :icon_wink: