My radio shows the Message LOC on the screen, after checking the manual I could not get into the settings to un lock it.
With the engine off I tried the run position on the ignition cylinder whiile pushing the 1 & 4 buttons, no change...
Also I read that there is Special code needed that I do not have.
Can anyone tell me how to get into the settings and then what code to use..
Gary

I took this to the dealer and they needed to get a code off the radio and call into GM for a unlock code....
I was told that they see this every couple of months from their customers.

My guess is you bought the truck used and the previous owner set the code and didn't tell you when you bought it. I had this problem with my VW but the crazy Germans program it to where it only locks if it doesn't recognize the car its in. When I replaced my battery and turned it back on, it said locked, but it recognized the car and unlocked itsself.