I've searched and found the basic programming instructions for the 03. Mine doesn't react the same way...the locks cycle (up and down) and gives a short horn beep EMMEDIATELY after I turn it ON, OFF, ON, OFF. And when I release the unlock switch it does it again. What does this mean? I got my 03 used and it didn't come with remotes (it was a repo). How can I tell for sure if it even has a receiver and is set up for keyless entry. Seems that it's acting like it does if it responds (albeit incorrectly) to the programming in this manner. TIA!

Do you have remotes? Have you gone through the whole procedure yet?

Try it, see what happens. Only takes about a minute--minute and a half.

Yeah, I actually have 4 remotes, 3 number Ones and 1 Number Two. I went through the entire procedure, but nothing happens when I hold down the buttons (I hold it down for nearly a minute to be sure) and I changed all the batteries.

My experience is limited to two Trailblazers, and both had at least one remote to begin with.

Sorry I can't help more.

Do you have the correct remotes for your Trailblazer? They have to be the MYT3X6898B remotes, not LHJ011 like many people have listed wrong on ebay.

i have the same problem with my truck..i dont know what it means..but i need help i have the MYT3X6898B remotes...i did the same on,off,on,off then it beeps and locks and unlocks..after i held the lock and unlock bottons down the truck does a lock cycle.."like it should do right?" then i turn the truck on to exit the program mood and try the keys and they dont work..