Brake Assist; Hill Start Assist (Hsa); Parking Brake - GMC 2014 Sierra Owner's Manual

Driving with the parking brake on
can overheat the brake system
and cause premature wear or
damage to brake system parts.
Make sure that the parking brake
is fully released and the brake
warning light is off before driving.
To release the parking brake, hold
the regular brake pedal down, then
push down momentarily on the
parking brake pedal until you feel
the pedal release. Slowly pull your
foot up off the parking brake pedal.
If the parking brake is not released
when you begin to drive, the brake
system warning light will flash and a
chime will sound warning you that
the parking brake is still on.
If you are towing a trailer and are
parking on a hill, see
.
This vehicle has a brake assist
feature designed to assist the driver
in stopping or decreasing vehicle
speed in emergency driving
conditions. This feature
automatically 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.
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).