Four-Wheel-Drive Light - GMC 2012 Sierra Denali Owner's Manual

{
WARNING
The brake system might not be
working properly if the brake
system warning light is on.
Driving with the brake system
warning light on can lead to a
crash. If the light is still on after
the vehicle has been pulled off
the road and carefully stopped,
have the vehicle towed for
service.
If the light comes on while driving,
pull off the road and stop carefully.
The pedal might be harder to push
or might go closer to the floor. It can
take longer to stop. If the light is still
on, have the vehicle towed for
service. See Towing the Vehicle on
page 10 87.
Antilock Brake System
(ABS) Warning Light
For vehicles with the Antilock Brake
System (ABS), this light comes on
briefly when the engine is started.
If it does not, have the vehicle
serviced by your dealer. If the
system is working normally the
indicator light then goes off.
If the ABS light stays on, turn the
ignition off. If the light comes on
while driving, stop as soon as it is
safely possible and turn the ignition
off. Then start the engine again to
reset the system. If the ABS light
stays on, or comes on again while
driving, the vehicle needs service.
If the regular brake system warning
light is not on, the vehicle still has
brakes, but not antilock brakes.
Instruments and Controls
If the regular brake system warning
light is also on, the vehicle does not
have antilock brakes and there is a
problem with the regular brakes.
See Brake System Warning Light on
page 5 24.

Four-Wheel-Drive Light

For vehicles equipped with the
four-wheel-drive light, it comes on
when a vehicle with a manual
transfer case is shifted into
four-wheel drive and the front axle
engages.
Some delay between the shifting
and the light coming on is normal.
See Four-Wheel Drive on page 9 39
for more information.
5-25