I'd appreciate help with my '99 Blazer 4 door 4WD. My driving lights quit working completely, however the brights work and the daytime running lights work. I checked the bulbs and ground, both ok. The light switch and the dimmer both are ok (I've already replaced the multifunction switch once).

The fuses are ok, I was wondering if there are any relays/circuit breakers I need to check. Or any other ideas?

thanks much, I rigged the brights into the driving light positions for a temp fix, but obviously this isn't ideal.

Rob

 

Did you check the fuses in the BCM in the engine bay?

 

I'm not sure what BCM stands for, but I did check the fuses in the engine compartment fuse box, the two 15 A fuses there for the left and right headlamps were fine.

 

There is a relay for the low beams as well. It may be labeled HDM.

 

Thanks for the suggestions:

My low beams started working again, with no help from me. When I disconnected the ground to the under hood fuse relay and then hooked it back up the low beams started working again. I noticed that the electrical systems, clock, etc had reset so I assume something in the BCM got reset.

Is this a reasonable explanation? Any ideas on why this happened?

thanks,

Rob

 

Possibly corrosion on the ground keeping it from making a good clean connection?