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Black plate (47,1)
GMC Sierra Denali Owner Manual (GMNA Localizing-U.S/Canada/Mexico-
7299750) - 2015 - CRC - 6/9/14
Driving and Operating
9-47
Brake Assist
The Brake Assist feature is
designed to assist the driver in
stopping or decreasing vehicle
speed in emergency driving
conditions. This feature uses the
stability system hydraulic brake
control module to supplement the
power brake system under
conditions where the driver has
quickly and forcefully applied the
brake pedal in an attempt to quickly
stop or slow down the vehicle. The
stability system hydraulic brake
control module increases brake
pressure at each corner of the
vehicle until the ABS activates.
Minor brake pedal pulsation or
pedal movement during this time is
normal and the driver should
continue to apply the brake pedal as
the driving situation dictates The
Brake Assist feature will
automatically disengage when the
brake pedal is released or brake
pedal pressure is quickly
decreased.
Hill Start Assist (HSA)
This vehicle has an HSA feature,
which may be useful when the
vehicle is stopped on a grade. This
feature is designed to prevent the
vehicle from rolling, either forward or
rearward, during vehicle drive off.
After you completely stop and hold
the vehicle in a complete standstill
on a grade, HSA will automatically
activate. During the transition period
between when you release the
brake pedal and start to accelerate
to drive off on a grade, HSA holds
the braking pressure for a maximum
of two seconds to ensure that there
is no rolling. The brakes will
automatically release when the
accelerator pedal is applied within
the two-second window. If the
vehicle is equipped with the
Integrated Trailer Brake Control
(ITBC) system, HSA may also apply
the trailer brakes.
It will not activate if the vehicle is in
a drive gear and facing downhill or if
the vehicle is facing uphill and in
R (Reverse). There may be
situations on minor hills (less than
5% grade) with a loaded vehicle or
while pulling a trailer where HSA will
not activate.
If you release the brake pedal and
then reapply the brake pedal while
HSA is activated, the brake pedal
typically feels firmer with less pedal
travel.