2001 GMC Sierra 1500 Pickup Owner's Manual - Page 217

(5): Press this pushbutton to turn Dolby NR on and off. Dolby NR is active when a tape is inserted in the remote cassette. The double-D symbol will appear on the display. Dolby Noise Reduction is manufactured under a license from Dolby Laboratories Licensing Corporation. Dolby and the double-D symbol are trademarks of Dolby Laboratories Licensing Corporation. FWD (6): Press this button to rapidly advance the tape. The tape will rapidly advance to the end of the cassette reel or until you press FWD again. The radio plays the last selected station during FWD. PROG: Press this button on the remote player to go from one side of the tape to the other. TAPE: Press the AM-FM button to switch from the player and the radio when a tape is playing. To return to the tape player, press CD AUX. The lighted arrow will appear next to the symbol and show the direction of play when a tape is active. EJECT: Press this button on the remote player to remove the tape. EJECT can be used with either the ignition or radio off. Also, you must press EJECT before loading a cassette with the radio off to allow loading. Theft-Deterrent Feature (If Equipped) THEFTLOCKR 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 for the 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 has been interrupted. If your battery loses power for any reason, you must unlock the radio with the secret code before it will operate. Activating the Theft-Deterrent Feature The instructions which follow explain how to enter your secret code to activate the THEFTLOCK system. It is recommended that you read through all nine steps before starting the procedure. If you allow more than 15 seconds to elapse between any steps, the radio automatically reverts to time and you must start the procedure over at Step 4. 3-30