2007 GMC Sierra 1500 Pickup Owner's Manual - Page 215

An arrow on the instrument panel cluster will flash in the direction of the turn or lane change. Turn Signal On Chime If your turn signal is left on for more than 3/4 of a mile (1.2 km), a chime will sound at each flash of the turn signal and the message TURN SIGNAL ON will also appear in the Driver Information Control (DIC). To turn the chime and message off, move the turn signal lever to the off position. As you signal a turn or a lane change, if the arrows flash more quickly than normal, a signal bulb may be burned out and other drivers will not see your turn signal. If a bulb is burned out, replace it to help avoid an accident. If the arrows do not go on at all when you signal a turn, check for burned-out bulbs and a blown fuse. See Fuses and Circuit Breakers on page 600. Headlamp High/Low-Beam Changer 53 (Headlamp High/Low Beam Changer): To change the headlamps from low to high beam, push the lever toward the instrument panel. To return to low-beam headlamps, pull the multifunction lever toward you. Then release it. When the high beams are on, this indicator light on the instrument panel cluster will also be on. 215