TURNING ON LIGHTS KILL ELECTRICAL

[radioactivelarry]

Developed this weird problem, when I pull on the light switch the entire electrical system shuts down. The engine quits and nothing electrical works, I mean nothing! When i push the light switch back off everything returns to normal. the engine will start and run. The lights never come on either.
I have checked the charging system and the alternator is putting out and the battery is up to normal. I checked all the fuses the first time it happened when I got stuck in traffic. I wiggled the wires and checked the battery connections and the only thing I did was to pull the battery cables and check and re-tighten the terminals.

Could it bee the light switch itself? I must mention there is no smoke or burning wire smell at all. Anyone ever have this happen to them? I can't drive my truck at night until I figure this out.

All helpful suggestions will be greatly appreciated.

Thanks all.....

[basketcase0302]

"radioactivelarry"]Developed this weird problem, when I pull on the light switch the entire electrical system shuts down. The engine quits and nothing electrical works, I mean nothing! When i push the light switch back off everything returns to normal. the engine will start and run. The lights never come on either.
I have checked the charging system and the alternator is putting out and the battery is up to normal. I checked all the fuses the first time it happened when I got stuck in traffic. I wiggled the wires and checked the battery connections and the only thing I did was to pull the battery cables and check and re-tighten the terminals.

Could it bee the light switch itself? I must mention there is no smoke or burning wire smell at all. Anyone ever have this happen to them? I can't drive my truck at night until I figure this out.

All helpful suggestions will be greatly appreciated.

Thanks all.....

More than likely the switch causing a "dead short" / direct ground. Try unplugging the headlight switch wiring harness, (once you've unhooked the battery) then drive or run the truck for awhile to see if it duplicates itself but I 2nd the switch itself being the culprit here.

[MadMike]

I'll 3rd the light switch, the older they are they weirder stuff they do.
Although I am impressed by its ability to kill the whole electrical system.
May want to check your ignition switch contacts have not been damaged by an excessive amp draw.

[radioactivelarry]

The switch sounds plausible, I was also thinking the voltage regulator could be bad also, however I never had a fluctuation with the lights going bright or dim.

I installed a all new ignition switch/key about 16 months ago but I will check it also. I don't have an AMP gauge so I can't see a short draw. Probably should install one now when I replace the light switch. luckily the switch is still available.

Thanks for all the suggestions.....Will post the outcome....

[radioactivelarry]

Turns out the positive battery cable was bad and also corroded (rusty) at the terminal where it connects to the solenoid. Replaced all 3 cables, cleaned all connections and I'm in business. just for the heck of it I installed a new "MADE IN USA" battery that is made in Pennsylvania with new lead. Lots of cranking amps and the the big 390 spins right over! Now I'm a happy camper and "back on the road again".....

Installed a three gauge set with a volt meter. Lots of volts and oil pressure is over 60 lbs and water temp running at 195, just where the FE engines like to be...

Now I'm installing my new Holley 600 CFM carb and four barrel intake along with headman Headers and Flowmaster exhaust. It already has a cam so now I will unleash it's potential. Gonna tow my boat with no problem....

Thanks for all the comments.

[Lee]

Thanks for the follow up!!!!!

[72_Ranger_Theo]

Same thing happened to me a few weeks ago. Turned on the headlights, the engine shut off. I just happened to be at a mechanic friend's house and he took a good look at it. He said, "your batter cables are corroded." Now, mind you, they weren't outwardly very bad. No massive green meringue. But inside they were corroded. So, just today I got new cables from O'Reilly's. Took the old ones off, no problem. But when I tried to put the 48" black negative cable on the engine, I realized the bolt was way too big for the end. So I put the old ones back on. Called my mechanic friend, and he said he could fix a metal plate with a big hole for the big bolt to go in, and a smaller hole for the cable end to go through. He's done it before and it works fine, he said.

[basketcase0302]

Same thing happened to me a few weeks ago. Turned on the headlights, the engine shut off. I just happened to be at a mechanic friend's house and he took a good look at it. He said, "your batter cables are corroded." Now, mind you, they weren't outwardly very bad. No massive green meringue. But inside they were corroded. So, just today I got new cables from O'Reilly's. Took the old ones off, no problem. But when I tried to put the 48" black negative cable on the engine, I realized the bolt was way too big for the end. So I put the old ones back on. Called my mechanic friend, and he said he could fix a metal plate with a big hole for the big bolt to go in, and a smaller hole for the cable end to go through. He's done it before and it works fine, he said.

Yeah that'll work or you can go the easy route and just get the proper terminal end cheaply which takes about two minutes to replace:

https://www.ebay.com/itm/5-LOT-4-AWG-Ri ... 0005.m1851