Ignition key won't turn
 

Strange thing happened yesterday. I noticed the ignition key didn't seem to slide into the ignition quite as easy as normal. When I went to start, the key flat out would not turn! I wiggled the shifter handle, depressed the brake, wiggled the key, pulled it out, put it back in...nothing! Locked solid! I called the dealer, and he was ready to send a flatbed to haul me in. While talking to him, I kept playing with the key and finally it turned. The dealer said no point in bringing it in if the problem went away, but now I'm worried about getting stranded. Anyone else ever see this? :confused:

I had this happen to me. I had a remote start/ car alarm installed and they botched the install the pulled some wires too tight that are connected to my shifter. The wire eventually started breaking due to the movement of the shifter going from park to drive. This was causing the truck to think the shifter wasn't in park and the key wouldn't turn. It would take me 5-10 minutes of fiddling with the shifter sometimes to get the key to turn. I finally had enough the last time it did it to me and I drove it to the dealer and left it there for them to troubleshoot.

They found the wire and told me the cause and even though the issue was actually caused by the remote start install, they still fixed it under warranty. I did have to take it back and have my remote start fixed, because after the dealer fixed my key turning issue, my remote start quit working. lol

Had the same happen to a friend's Tahoe 2008. He'd used his key to cut open some duct-tape from a package & apparently some debris had gone into the key hole. WD40 helped sort it out (quick fix) Dunno if that helps...

And yeah, he's never used his key for anything other than his car ever since :)

H3 Ignition Key Will Not Turn
 

Thought I'd share my experience here in the event it's not an isolated event:

Bought an 2008 H3 about 3 weeks ago, and the dealer only had one key so I had the local Hummer dealer make me another one. The Parts Dept. person said that the H3 keys are a higher grade steel than most keys and his machine strains to cut them. He told me it might not fit exactly but to wiggle it a bit initially and it should work with a little effort.

Sure enough, the key took a little bit of extra force to turn the ignition the first time, but after that it worked normally. I didn't use the key after that, instead using the original he cut the key from.

4 days later, after several starts and stops, I put the original key in the ignition and the ignition switch would not turn at all. I made sure the shifter was in park and wiggled the key all kinds of ways to get it to align in the tumbler but no luck. I tried the other key also, and it wouldn't work either.

After several hours off and on of attempting to get it to work, I had to call GM Roadside Assistance to have a rollback truck haul it to the Hummer dealer. We had to get under the vehicle and unhook the transmission shift linkage to get it on the truck without damaging anything also.

They couldn't get it to work either, and ended up replacing the ignition switch assembly, re-keying another key as a test, and also replaced the door lock because none of the keys would work in it either for some bizarre reason.

Even though they didn't say so, my theory is the tumbler spring in the ignition or the tumbler itself was damaged, but who knows what happened with the door lock and keys.

It was covered under warranty, but it took nearly a week to get all of the parts in and get everything replaced. Weirdest issue I've ever experienced, but just an FYI - be careful with using replacement H3 keys.