Curse this infernal wiring!!

[Bobert]

I swear, EVERY time I fix something electrical on this blazer, something else breaks in 1 week or less.

This time, the starter wouldn't start the engine. It sounded like It wouldn't enguage the teeth on the flywheel. So I took it off, looked at it, smelled it, put it back in and it works just fine. I won't pretend I know why.

Last night, my driving lights went out. And there were plenty of friendly people that enjoyed reminding me.

So I hopped on this site, and found a burnt fuse. It was a 20, but I put in a 30amp ( which I read it should be).

For future reference, make sure the light switch is off or it will spark when you are upside down trying to put in the fuse.

That did the trick! so a bit later, I started it to warm up, put the lights on, backed out and I think right when I braked to put it into drive, The fuse burnt out again.

For now, It drive just fine in the daylight and snow. I am still looking over past threads and TM's.
I'd bet that all these problems are related, and I am scared what will break next. I hope it is something I can live without and just end the chain.

Sorry, this is kind of a rant. I don't know what I would do without this support group.

 

[Bobert]

I guess a little backround, It has been very cold and very, very wet around here. I had to drive the cucv today because the parking brake on my truck was frozen. I don't know if that makes any difference.

 

[Blood_of_Tyrants]

Your fuse blew because there is a short in the wiring. Obvious places to look is anywhere the wire might be rubbing against metal.

 

[ida34]

I had a short in the back were the harness goes up to the tail lights behind the bumper. I would check there 1st. I had lights except the headlights blow when I put on the brakes. Naturally the brake light feed was the one shorting to ground.

 

[Bobert]

hmmm... I was afraid someone would say that. A ground problem could be the bane of my existence. The search begins!

 

[Bobert]

Thanks Chuck, I wouldn't have thought of anything back there.

 

[n1bnc]

I had a problem with my 76 2wd 6cyl Blazer with the 3 on the tree. The rear cable managed to land on the exhaust and kill the tailighting. I had no idea until a fellow in blue told me. The next day I found the rear cable in a Suburban on top of two other trucks and pulled it, plugged it in and drove away. The Sub was a bit bouncy up there!

 

[tsmall07]

I'm having the same light problem as you are. Let me know when you fix it and I'll do the same. I hate electrical problems.

 

[crusty]

Try using a light bulb with leads and male 1/4" spade lugs to temporarily replace your fuse while troubleshooting. It will save a lot of aggravation.

 

[Bobert]

Good ideas guys. Right now, the parking lot it's in is a 1-2inch sheet of ice. So as soon as I find a dry place I'll get on it.

Right now, my brake lights work but not the running lights. It acts as if the Blackout switch was flipped. (but it's not).

Tsmall, I feel your pain. I read your thread too. I'll be sure to post anything I figure out to help you and future victims.

Crusty, I even have a dc trouble light that I got out of the dupster at the local base. haha good thinking

 

[CCATLETT1984]

fyi, if the blackout light switch is tripped, the brake lights dont work either.

 

[ken]

I had the same headlight problem on a 83 chevy pick up. Make sure the ground from the firewall to the engine bell housing is still there and it's clean and tight. That cured my problem. Hope it helps.

 

[Bobert]

Well I looked under the hood and under the body front and back and didn't see anything obvious.

I did find on of my batteries on its side. Must have been when I di that barrel roll. That didn't do anything with the lights but it is fine even though it sat like that for 3 days (take that stupid optima batteries!).

I didn't check by the bell housing but that will be next. It is dumping snow right now so I hope I can get it inside to look at it.

 

[Bobert]

Okay, after many nights of racing home before sunset, I now have headlights.

Not exactly sure what i did, but I just jiggled and untwisted the wires that plug into the headlights and turn signals.

So, keeping with tradition, now I have no running lights lights. I have headlights, all the signals, and breaklights. But they dont come on when I have the headlghts on.

So I still will get pulled over if a cop sees my backend.

I'm wondering if this is a switch deal? or just another wire? tsmall, did you figure yours out?

 

[Bobert]

OK turns out the running lights go through a different fuse. I should have checked the diagram.

Everything works (for now). I'll have to drive it and see if it burns out or not. Maybe I'll go to the parts store to stock up on 30amp fuses!

 

[tsmall07]

Hey, I did figure mine out the other day. Mine was only due to the 30 amp fuse blowing. The overall cause was that the battery tray had fallen down and chaffed the wires going to the headlight. They were grounding out on the tray. I've got 15 30A fuses in my glove box now. They're really cheap and it sure beats having to drive home with a mag light through the windshield again...

 

[Bobert]

Yeah I thought about taping a couple mag lights to the hood...
The wires I wigglled were in the same place but they burnt out after a while. I think I'm close though!

 

[Bobert]

This is strange. After fixing another starter problem, I am back to the lights.

I let it idle for around 15 minutes, with the lights and hazard flashers going and it worked just great. So I figure I'll take it on a test run, back out up my icy driveway and and go to put it in drive and my lights are out. the flashers stopped to but every time i press the brakes, the turn signals in the dash light up. I can't remember if it should do that or not.

I wonder now, if it could be something in the brake light wiring or maybe the backup lights. maybe I will back it it so I don't have to put it in reverse.

Still nothing obvious.

 

[CCATLETT1984]

with the hazards on, if you hit the brakes the lights on the dash will stay solid until you let off the brake pedal.

 

[tsmall07]

Take your front battery tray out and make sure that head light and blinker wiring isn't exposed and grounding out to the battery tray.