Cant turn key

Chek the battry shoud be discharge

Replace the lock and tumbler. If your truck has anti-theft, specifically a pass lock system. You'll have to take it to the dealer to recalibrate your key. There's a computer chip in the inside of the key. If the head of the key has a large plastic cover, most likely it's a pass lock, if not, you can remove the lock and tumbler by remove the column covers and pressing the small button at the bottom of the tumbler casing while key in is the "on" position. To install, reverse of removal.

To get it out, I had to pop off this little cap thing under the steering wheel column and there would be a button inside that would release the key, If this did not work then you need to contact GMC service center ....

Hi

take a Check at the main fuse maybe you have a defctive fuse!

Thanks!