2005 Trailblazer intermittent low beam headlamps

2005 Trailblazer....had intermittent low beam headlamps about a year back.....sometimes 1 was out, sometimes both were out, sometimes both were on. I was confused, but replaced both headlamps and the problem went away....till now.

Now Both are either on or off intermittently. Found the issue to be relay #46 in the under-hood relay/fuse box. Relay is labeled "HDM" . can anyone tell me what "HDM" stands for.....my guess would be Headlamp module, but I am guessing that is wrong. Anyway long story short, problem solved for $37.00 at autozone. The factory manuals continue to pay for themselves...

Hope this post helps someone with a similar issue

I was wondering what you found.Was headlamps dimming also?

in the 2nd paragraph of the original post the solution is given. It was the SSR (solid state relay) #46 labeled HDM......located in the underhood relay/fusebox, right side fender