1996 GMC Safari Owner's Manual - Page 147

P.SET PROG: The front passengers must be listening to something different for each of these three functions to work: Press this button to seek through your preset radio stations set on your primary radio pushbuttons. When a cassette tape is playing, press this button to go to the other sideof the tape. Theft-Deterrent Feature THEFTLOCK" is designed to discourage theft of your radio. It works by using a secret code to disable all radio functions whenever battery power is removed. The THEFTLOCK feature forthe radio may be used or ignored. If ignored, the system plays normally and the radio is not protected by the feature. If THEFTLOCK is activated, your radio will not operate if stolen. When THEFTLOCK is activated, the radio will display LOC to indicate a locked condition anytime battery power is removed. If your battery loses power for any reason, you must unlock the radio with the secret code before it will operate. VOL: Press this knob lightly so it extends. Turn the knob clockwise to increase volume and counterclockwise to decrease volume. Push the knob back in when you're not using it. The upper VOL knob controls the upper headphone and the lower VOL knob controls the lower headphone. 3-23