Hill descent control
Note: Each gear has a pre-determined
minimum speed.
BRAKE TEMPERATURE
In extreme circumstances, the HDC system
may cause brake temperatures to exceed their
pre-set limits. An HDC warning will be
Descent speed will increase only when a slope
is steep enough to provide additional
momentum. Therefore, use of switch (2) on a
gentle slope may not increase the speed.
displayed in the message centre. HDC will then
fade out and become temporarily inactive.
If the brake pedal is depressed, HDC will be
overridden and the brakes will operate as
normal. When the brake pedal is released, HDC
will resume control of the descent.
Once the brakes have reached an acceptable
temperature, the message will disappear (or
the warning indicator will extinguish) and HDC
will, if required, resume operation.
If HDC is switched off during a descent, HDC
will fade out gradually. This is to prevent loss
of control if HDC is switched off in error.
SYSTEM FAULT
If a fault is detected in the HDC system, an HDC
warning will be displayed in the message
centre.
HDC will resume control when switched back
on, at the standard default speed.
If the fault is detected while the system is
operating, HDC will then fade out.
Do not attempt a steep descent if HDC
is inoperative or warning messages
are displayed.
If a fault is detected, contact your Land Rover
Dealer/Authorised Repairer as soon as
possible.
GRADIENT RELEASE CONTROL
(GRC)
AUTOMATIC SYSTEMS
With HDC activated, if the vehicle is stopped on
a slope using the foot brake, GRC will become
active (except in Terrain Response Sand
program). It operates in all gears and in neutral
position.
Gradient Acceleration Control (GAC) and Hill
Start Assist are not active while HDC is
operating.
GAC will limit vehicle acceleration on steep
descents, allowing the driver to feel more in
control of the vehicle.
During a steep hill descent, when the foot brake
is released GRC will automatically hold brake
force for a short period before gradually
releasing it, allowing for maximum control to
be retained.
Hill Start Assist activates when starting a hill
ascent from a stationary position. When the
foot brake is released Hill Start Assist smoothly
releases the brake pressure, allowing the
vehicle to move away without rolling
backwards.
During an uphill start, a similar brake hold and
gradual release is employed. This allows time
for the driver to apply speed and allow the
vehicle to move away smoothly.
Any fault with GAC or Hill Start Assist will be
indicated by the DSC warning lamp being
illuminated and a message in the message
centre.
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