I bought a 1996 blazer off craigslist a few days ago and its been a nightmare. I fixed so much it should be brand new but what i cant figure out is: when you turn the driving lights on, nothing happens at all. Turn the head lights on and the driving lights still dont work just headlights. I bought a new switch and still same problem. I checked all visible wires and they all look healthy. So i ran a wire from headlights to the brown wire and now when you turn the headlights on all lights come on. Still have no idea why driving lights dont work on there own. I was leaving to home tonight when i turned the headlights on i noticed the 4wd button lights turned on. The 4wd only works when the headlight switch is turned on. Im stumped now so maybe someone can please help?
I checked all relays and fuses plus that wasted new switch

 

When you say "driving lights" do you mean the factory fog lamps, or the head lamps?


The Brown wire is for park lamps, tail lamps, and dash illumination, that's why all those lights come on when you turn the headlamps on. Better remove the wire you installed. Without removing the fuses, check both terminals of all fuses with a test lamp, or volt meter. Must show battery voltage on both sides of the fuse. The "tail lamp" fuse will not show voltage unless the headlamp switch is turned on.