2007 GMC Acadia Owner's Manual - Page 223

Anti-Lock Brake System Warning Light Your vehicle has the Anti-Lock Brake System (ABS). This light will come on when your engine is started and may stay on for several seconds. This is normal. Turn the ignition off. Then start the engine again to reset the system. If the light still stays on, or comes on again while you are driving, your vehicle needs service. If the regular brake system warning light is not on, you still have brakes, but you do not have anti-lock brakes. If the regular brake system warning light is also on, you do not have anti-lock brakes and there is a problem with your regular brakes. See Brake System Warning Light on page 222 earlier in this section. The ABS warning light will come on briefly when you turn the ignition key to ON. This is normal. If the light does not come on then, have it fixed so it will be ready to warn you if there is a problem. If the light stays on, turn the ignition to off. If the light comes on and the chime sounds when you are driving, pull your vehicle over to a safe location and stop as soon as possible. 223