Am new at this and am trying to get a hold of someone who knows. I have 1999 Blazer. DRL's quit, now headlights on all the time. Has auto headlights. Is there a fuse for the DRL's? I can't find anything in the fuse boxes that say DRL. Went out this morning and started the truck, DRL's worked for about 2 minutes then headlights came back on again. AARGH! Thank you in advance.

 

Sounds like they're working properly. Was it shadey or low light, how about a notepad or something on the dash that slid across to the PS speaker on the dash? On that speaker is a black nipple of sorts, that's the DRL Sensor. If it gets covered the headlights turn on.

 

Nope, bright sunlight. Nothing on dash...

 

Sounds like y our ambient light sensor is the problem, not the DRLs.