Just picked up a 98 Chevy Blazer 4x4 Saturday the dash lights aren't coming on but the headlights come on automatically when I turn the truck on and I can't turn them off or on with the switch was wondering if it was a bad switch? For the dash lights to come on I have to roll the dimmer switch up for them to turn on then it turns all the interior lights on anybody know what that is?

 

As far as the headlights go, they're automatically on at a certain level of darkness. Unfortunately the only way to turn them off with the switch would be to install the resistor at the sensor located in the passenger side dash speaker housing. I've owned several of these and some models allow you to push the dome override button in and out a couple of times and it will disable the auto-on feature. I don't think 98 was a year that had it. The dash lights only coming on with the dimmer all the way to interior lights on may be a faulty or dirty dimmer. You could try cleaning it up and see if that helps.