GMC 2007 Acadia - 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.
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.
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.
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