I have a 89 trans am, with a AM/FM stereo w/ cassette & remote controls on steering wheel, that says "Loc" on radio panel. Owners manual says to push mute button on steering wheel. That didn't work!
Anyone have the same problem?
Thanks..Gary

 

I have an 89 gta with the delco radio that did the same thing.
Its the theft protection. You get that Loc message when the battery is disconnected for awhile.
It is the mute button on the steering wheel that cures this, I had to do it myself once about 10 years ago.
I seem to remember you start up the car then hold in the mute for like 10 secs. Something like that.
Here's more description

 

Thanks oahawool!
The articule was very helpful...Gary