i would try that first, many people with the HUD have that problem with the weak solder spot

The smacking it could rattle things up to the HUD. Jump the power wire on the switch over and see if it makes a diff first. Alot easier than tearing the dash apart...

Yeah, I think it'* your issue.

"All this started when I took the dash apart to take the radio out for some bulb soldering."

What were you repairing on the radio???

I have some issues with dimmed or non working segments on the right half of the display. Sometimes a light tap with a fingertip will make part of the involved segments work. Just wondering if this was the area you were working in.

don't have a hud switch but i have a spare hud, fog light switch, hazard switch headlight switch and such

honestly look into the HUD solder, its a well known issue with them, i'm sure theres a writeup on almost every forum about it

Thanks for all the responses guys. It seems to be working great for the last couple of days, and I'm not going to tempt fate by messing with it right now. When it starts acting up again (definitely when not if) I'm will remove the HUD and fix the joint.

Jax, It sounds like one of those common Pontiac radio problems, you've got soldering in your future. The lights in our radio are notorious for burning out and the only solution other than an aftermarket deck is to take the unit apart and replace the bulbs. There is a great write up on the topic in this forum, just do a search.