My brothers 92' Blazer (4.3L CPI) stalled right after he put the headlights on. The motor was running, tranny was in drive and rolling. I checked all the fuses to see if there was a popped one, didn't see any popped ones. Right now the headlights will not turn on nor the taillights (brake lights still work), the radio and interior lights also are not working. It turns over perfectly normal but will not start, battery terminals are nice and tight. It has not started once before when it was cold out but the headlight problem seems rather odd. Is there another fuse box that I'm not seeing or maybe a fuse I missed? A little help will be greatly appreciated.
Thanks, Tony

 

As far as the vehicle not starting, did you do any of the basic tests? With the engine cranking, check for spark at the plugs, if you have good spark, check fuel pressure.

The headlamp switch gets voltage from two sources, one is the fuse box, T/L courtesy fuse. Not only would you check the fuse, you would check that one of the terminals where the fuse plugs in, is hot. If one of those terminals isn't hot, a good fuse won't matter.

The other source may come from a junction block under the hood, follow the positive battery wires/cable, see if it leads to a junction block, may be several fusible links. One way to test a fusible link, there should be voltage on both sides of the link. Sorry, I don't have a wiring color in front of me.

 

It is not getting spark and the fuel pump is not running. It has done this before, BUT, after I would let it sit for a couple hours it would turn back on and everything would be running just fine. This is the third time it did it in 4months, but this time it's not fixing itself.. Is there a relay where the lights, and ignition go through. Might be sticking but I have no which one it is.