2012 GMC Sierra Owner's Manual - Page 58

2-14 Keys, Doors, and Windows 4. Insert the new key to be programmed and turn it to the ON/RUN position within five seconds of turning the ignition to the LOCK/OFF position in Step 3. The security light will turn off once the key has been programmed. 5. Repeat Steps 1 through 4 if additional keys are to be programmed. If you lose or damage your PASS-Key III+ key, see your dealer or a locksmith who can service PASS-Key III+ to have a new key made. Do not leave the key or device that disarms or deactivates the theft-deterrent system in the vehicle. Exterior Mirrors Convex Mirrors Manual Mirrors If the vehicle has manual mirrors, they can be adjusted by moving the mirror up and down or left to right to see a little of the side of the vehicle, and have a clear view behind the vehicle. Using hood-mounted air deflectors and add-on convex mirror attachments could decrease mirror performance. { WARNING A convex mirror can make things, like other vehicles, look farther away than they really are. If you cut too sharply into the right lane, you could hit a vehicle on the right. Check the inside mirror or glance over your shoulder before changing lanes. The passenger side mirror is convex shaped. A convex mirror's surface is curved so more can be seen from the driver seat.