Ford Ranger Owner's Manual page 101

Hill descent control (HDC)
Note: Descent speed will only increase on
a slope steep enough to provide additional
momentum. Therefore, use of the + switch
on a gentle slope may not increase the
speed.
Note: 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.
Note: If HDC is switched off during a
descent, HDC assistance will fade out
gradually. This is to prevent loss of control
if HDC is switched off in error. HDC will
resume control when switched back on if
assistance is still required, but at the speed
the vehicle is travelling when the pedal is
released.
When driving off-road HDC can be
permanently selected, but it will only
provide assistance when the speed
parameters are met.
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