
Driving and Driving Safety
193
The limits set by the physics of driving cannot be
overcome, even with the HOLD function.
Responsibility for driving off on upward slopes is
still the driver’s, despite the HOLD function.
Assistance by the HOLD function is not always
guaranteed when stopping and driving off on
a slippery surface (e.g. on icy or loose surfaces).
In this case, the vehicle can slip.
f
Always adjust your driving style to the driving
conditions and vehicle load. Use the footbrake
if necessary.
If the Drive-Off Assistant is not functioning, the
driver cannot be assisted when driving off on hills.
f
Hold the vehicle with the footbrake.
If the vehicle comes to a standstill on a steep
uphill gradient without using the service brake,
this may result in a certain roll-back before the
vehicle is held by the HOLD function. In this
situation, the driver can reduce the roll-back by
pressing the footbrake.
f
Assist holding of the vehicle by increasing the
braking force with the footbrake.
Brake pedal feels different. When adaptive cruise
control is operating normally or when the HOLD
function is active, the brake pedal may feel
different and you may hear hydraulic noises.
Pressing the footbrake while the HOLD function
is active can cause pulsations in the pedal.
This behavior is normal for the system.
It is not a fault.
Porsche Hill Control (PHC)
Porsche Hill Control is an assistance system that
helps the driver when driving slowly downhill at
speeds of between approx. 2 mph (3 km/h) and
20 mph (30 km/h), e.g. on steep slopes or on
wintry mountain roads, both when driving forward
and reversing.
The system limits the speed by braking on all four
wheels. ABS remains active to prevent the wheels
from locking.
On vehicles with manual transmission, the system
adapts the speed in such a way that the engine is
not braked at idle speed.
Like all brakes, the braking ability of Porsche
Hill Control is impaired on slippery surfaces
(e.g. on icy roads or loose surfaces).
Reduced braking ability on a slippery surface.
f
Always adjust your driving style to the driving
situation.
Preconditions:
– PHC is on.
– The speed must not exceed approx. 20 mph
(30 km/h).
– The gradient must be at least approx. 12 %.
– The driver does not accelerate or brake.
Limits of HOLD Function
Drive-Off Assistant Not
Working
WARNING
h
CAUTION
h
Vehicle Roll-back
CAUTION
h
Slippery Roads
WARNING
h