Hill descent control, Hill descent control (hdc) – BMW 325XI User Manual
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Hill Descent Control (HDC)*
The concept
By reducing the vehicle's speed on
steep downhill stretches, HDC main-
tains predictable vehicle handling
response to provide you with control of
your BMW during extreme descents.
The vehicle slows to a pace just slightly
faster than walking speed.
HDC is available for activation at vehi-
cle speeds below approx. 22 mph /
35 km/h. When driving down steep
hills, the vehicle reduces speed auto-
matically down to about double walking
speed – approx. 7.5 mph / 12 km/h –
and then maintains this speed at a con-
stant.
You can use the accelerator or brakes
to vary this speed within a range from
approx. 3 mph / 5 km/h to approx.
15 mph / 25 km/h.
In conjunction with the multifunction
steering wheel you can use the +/–
button to set the cruise control to a tar-
get speed in the range from approx.
3 mph / 5 km/h to approx. 15 mph /
25 km/h.
HDC is automatically deactivated once
vehicle speed again exceeds approx.
37 mph / 60 km/h.
To activate the system
Press the HDC button; the green indi-
cator lamp integrated within the button
comes on.
The indicator lamp flashes whenever
the system is actively intervening to
control your speed with automatic
brake applications.
To deactivate the system
Press the button again, the indicator
lamp goes out.
HDC is automatically deactivated once
the vehicle accelerates to more than
37 mph / 60 km/h, as well as whenever
you switch off the ignition.
To use HDC
With manual transmission:
You should always ensure that either
reverse or first gear is engaged before
using HDC, as the engine's braking
effect is most pronounced in these
gears, and only reduced engine braking
is available in higher gears.
With automatic transmission: HDC is
available for use in all ranges.
System malfunctions
Signaled by the indicator lamp, which
responds to problems by going out
while HDC is in operation or by failing
to come on when you activate the sys-
tem:
HDC is temporarily not available if
brake temperature is too high.
If the DSC indicator lamp comes
on at the same time:
There is a fault in the HDC and
DSC systems. Have your BMW center
inspect this system as soon as possi-
ble.
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