CITROEN C4 PICASSO Handbook page 166

Driving
The active cruise control operates by
day and at night, in fog or in moderate
rainfall.
The selection of this system deactivates
the inter-vehicle time function.
The system does not act on the braking
system, but works only with engine braking.
The regulation range is limited: there will
no longer be any adjustment of speed if the
difference between the programmed speed
setting and the speed of the vehicle in front
becomes too high (18 mph (30 km/h)).
If the difference between the
programmed speed setting and the
speed of the vehicle in front is too
great, the speed cannot be adjusted:
the cruise control is automatically
deactivated.
164
General points
The active cruise control is switched on
manually: it requires that the speed of the vehicle
be between 25 mph (40 km/h) and 90 mph
(150 km/h), as well as the engagement of:
- fourth gear or higher with a manual
gearbox,
- second gear or higher with an electronic or
automatic gearbox in manual mode,
- position A with an electronic gearbox or D
with an automatic gearbox.
If the speed setting selected is above
93 mph (150 km/h), the system switches
to standard cruise control operation
(a message appears in the instrument
panel).
The active cruise control cannot in any
circumstances replace the observation
of speed limits, nor the need for
vigilance on the part of the driver.
It is recommended that you always keep
your feet close to the pedals.
The active cruise control can above be paused
using the control, or automatically:
- by pressing the brake or clutch pedal,
- in the event of operation of the ESC, for
safety reasons,
- in the event of operation of the electric
parking brake control lever,
- when an inter-vehicle time threshold is
reached (calculated according to the
relative speeds of your vehicle and the
vehicle in front and the inter-vehicle time
setting chosen),
- when the distance between your vehicle
and the one in front becomes to small,
- when the speed of the vehicle in front is to
low,
- when the speed of your vehicle becomes
too low.
The inter-vehicle time setting is
memorised on switching off the ignition.