Over the last year or two every once in a while when I start the truck, none of the gauges turn on. All the back lights for them come on, but none of the needles move. Normally after say, 15-30 sec, they all come on and go through their start up sequence. I will say I noticed it more when it was cold then warm I think which would make sense if my batteries were getting low, but, I replaced one of them in the last couple years and didn't seem to notice anything different. Then, this past weekend, (it was probably 40's or 50's) I started it and it they didnt come on at all. I drove 5 miles to my buddies and shut it off. Came out 30 min later, started it and still nothing. After a couple more miles like that I slapped my hand down on top of the dash and wam, it woke up and has worked since. Based on that it would lead me to believe possibly a bad connection or bad ground somewhere. I know some people have had the min voltage threshold changed on their trucks.
Any other ideas out there?

Batteries or a loose connection.

Your cluster doesn't "wake up" due to the cranking voltage dropping below 10.5 volts. The batteries will need replaced after testing confirms this. Ignore the dash gauge for this problem, as it's not accurate enough for testing cranking voltage. 2003 trucks required 11 volts while cranking, hence the reflash to lower the "happy cluster" voltage. There is a reflash for an '03 that will lower the "wake up" voltage. And yes, all the idiot lights work even though the needles haven't "awoken".

There is also the possibility of corroded or loose battery terminal connections, sometimes under the removable terminal bolt.

Sounds like the same Issue I had on my 2003 2500 Avalanche. The gauges would not work but if I disconnected the battery and reconnected they worked. Did a few times then problem went away. Next winter cold again and it returned. Engine start was weak sounding weak so put in new battery. No more problem till traded. I do a check on it from time to time and seen new owner my 2nd cousin actually has replaced the cluster and looked like under a TSB for free. I check into that but not sure if they covered the trucks. Like mentioned the modules can be voltage sensitive and not wake up.

Also in future never replace only one battery. Replace in pairs. Granted it may test good but not like a new one so it will die before the replaced one and it could take the new one with it.

Brian

So, there are two new batteries in there now and it's still doing it. Actually, as of today, its worse. It used to wake up within a number of seconds, today it didnt wake up for a number of miles...Any thoughts? I know some of the older chevys had a problem with the connection behind the cluster just getting corroded, but those were pry early 90's or so.