1995 GMC Yukon Owner's Manual - Page 184

To Unlock THEFTLOCK After a Power Loss When battery power is reapplied to a secured radio, the radio won't turn on and "LOC" will appear on the display. Enter your secret code as follows. Pause no more than 15 seconds between steps. I. Turn the ignition on. 2. Turn the radio off. 3. Press MIN and "000" will appear on the display. 4. Press the MIN button again to make the last two digits agree with your code. 5. Press HR 10 make the first oneor two digits agree with your code. 6. Press AMPFM after you have confirmed that the code matches the one you wrote down. SEC appears in the display indicating that the radio is now operable. To Disable THEFTLOCK 1. Turn the ignition on. 2. Turn the radio off. 3. With the time showing in the display, press the I and 4 buttons together. Hold them down until "SEC" shows on the display. You are now ready to enter your secret code. Don't wait more than 15 seconds between any of the following steps. 4. Press MIN and "000" will appear on the display. 5 . Press the MIN button again to make the last two digits agree with your code. 6. Press HR to make the first one or twodigits agree with your code. 7. Press AM/FM after you have confirmed that the code matches the one you wrote down. - will appear in the display, indicating that the " system is unsecured (disabled). If the codeis incorrect, "SEC" will appear in the display and the system will still be secured. Theradio will still operate if it is secured or unsecured. If "SEC" appears and you still want to disable the system, follow the disable procedure again and enter the correct code. bb 3-24