2015.75 VAUXHALL ASTRA J sensor

Driving and operating183
Adaptive cruise control uses a radar
sensor to detect the vehicles ahead.
If no vehicle is detected in the driving path, the adaptive cruise control will
behave like a traditional cruise
control.
For safety reasons, the system
cannot be activated before the brake
pedal has been depressed once
since switching on ignition. Activation
in first gear is not possible.
Adaptive cruise control is mainly
advised to be used on long straight
roads, e.g. highways or country roads
with steady traffic. Do not use the
system if it is not advisable to
maintain a constant speed.
Control indicator A 3 118, m 3 118.
9 Warning
The complete driver attention is
always required while driving with adaptive cruise control. The driver stays fully in control of the vehicle
because the brake pedal, the
accelerator pedal and the cancel
switch have priority over any
adaptive cruise control operation.
Switching on
Press C to switch on adaptive cruise
control. The control indicator m
illuminates white.
Activation by setting the speed
Adaptive cruise control can be
activated between 31 mph and
112 mph.
Accelerate to the desired speed and
turn thumb wheel to SET/-, the
current speed is stored and
maintained. Control indicator m
illuminates green.
The adaptive cruise control symbol,
the following distance setting and set speed are indicated in the top line ofthe Driver Information Centre (DIC).

186Driving and operating
The green illuminated vehicle ahead
control indicator A is displayed in the
speedometer when the system
detects a vehicle in the driving path.
If this symbol does not display, or
displays briefly, adaptive cruise
control will not respond to vehicles
ahead.
Deactivation Adaptive cruise control is deactivated
by the driver when:
■ y is pressed.
■ The brake pedal is depressed.
■ The clutch pedal is depressed for more than four seconds.
■ The gear selector lever of automatic transmission is moved to
N .
The system is also automatically
deactivated when:
■ Vehicle speed slows down below 28 mph or accelerates above
120 mph.
■ The Traction Control system (TC) is
operating for more than
20 seconds.■ The Electronic Stability Control (ESC) is operating.
■ There is no traffic and nothing detected on the road sides for
several minutes. In this case, there
are no radar echoes and the sensor may report that it is blocked.
■ The collision imminent braking system is applying the brakes.
■ The radar sensor is blocked by an ice or water film.
■ A fault is detected in the radar, engine or brake system.
When adaptive cruise control is
deactivated automatically, the control indicator m illuminates white and a
warning symbol is displayed as a pop-
up in the DIC.
The stored speed is maintained.
9 Warning
When adaptive cruise control is
deactivated, the driver must take
over full brake and engine control.
Switching off
Press C to switch off adaptive cruise
control. The control indicator m
extinguishes. The stored speed is
deleted.
Switching off the ignition also
switches off adaptive cruise control
and deletes the stored speed.

Driving and operating187
Driver's attention■ Use adaptive cruise control carefully on bends or mountainroads, as it can lose the vehicle
ahead and need time to detect it
again.
■ Do not use the system on slippery roads as it can create rapid
changes in tyre traction (wheel spinning), so that you could lose
control.
■ Do not use adaptive cruise control during rain, snow or heavy dirt, as
the radar sensor can be covered by
a water film, dust, ice or snow. This reduces or suppresses completelythe visibility. In case of sensor
blockage, clean the sensor cover.
System limits ■ The system's automatic brake force
does not permit hard braking and
the braking level may not be
sufficient to avoid a collision.
■ After a sudden lane change, the system needs a certain time to
detect the next preceding vehicle.So if a new vehicle is detected, the
system may accelerate instead of
braking.
■ Adaptive cruise control does ignore
the oncoming traffic.
■ Adaptive cruise control does not brake for stopped vehicles,
pedestrians or animals.
Bends
The adaptive cruise control calculates
a predicted path based on the
centrifugal force. This predicted path
considers the current bend
characteristic, but cannot consider a
future bend change. The system may lose the current vehicle ahead or
consider a vehicle which is not in the
actual lane. This can happen when
entering or exiting a bend or if the
bend gets stronger or weaker. If it no
longer detects any vehicle ahead,
then control indicator A will
extinguish.
If the centrifugal force is too high in a bend, the system slows down the vehicle slightly. This braking level is
not designed to avoid spinning off the bend. The driver is responsible for
reducing the selected speed before
entering a bend and in general to
adapt the speed to the road type and
to existing speed limits.
Motorways
On motorways, adapt the set speed
to the situation and the weather.
Always consider that adaptive cruise
control has a limited visibility range, a
limited braking level and a certain
reaction time to verify if a vehicle is on
the driving path or not. Adaptive
cruise control may not be able to

188Driving and operating
brake the vehicle in time to avoid a
collision with a much slower vehicle or after a lane change. This is
particularly true if driving fast or if the
visibility is reduced due to weather
conditions.
While entering or exiting a motorway,
adaptive cruise control may lose the
vehicle ahead and accelerate up to
the set speed. For this reason,
decrease the set speed before the
exit or before the entry.
Vehicle path changes
If another vehicle enters your driving
path, adaptive cruise control will first
consider the vehicle when it is
completely in your path. Be ready to
take action and depress the brake
pedal, if you need to brake more
quickly.
Hill and trailer considerations
System performance on hills and
when towing a trailer depends on your
vehicle speed, vehicle load, traffic
conditions and the road gradient. It
may not detect a vehicle in your path
while driving on hills. On steep hills,
you may have to use the accelerator
pedal to maintain your vehicle speed. When going downhill, especially
when towing a trailer, you may have
to brake to maintain or reduce your
speed.
Note that applying the brake
deactivates the system. It is not
recommended to use adaptive cruise
control on steep hills especially when towing a trailer.
Radar unit
The radar unit is mounted behind the
radiator grille below the brand
emblem.
9 Warning
The radar unit was aligned
carefully during manufacture.
Therefore, after a frontal accident, do not use the system. The front
bumper may appear to be intact,
however the sensor behind can be
out of position and react
incorrectly. After an accident,

Driving and operating189consult a workshop to verify and
correct the adaptive cruise control sensor position.
Settings
Settings can be changed in the Auto
collision preparation menu in the
vehicle personalisation, 3 131.
Fault
If the adaptive cruise control does not work due to temporary conditions
(e.g. blockage by ice) or if there is a
permanent system error, then a
message is displayed in the DIC.
Vehicle messages 3 125.
Forward collision alert The forward collision alert can help to
avoid or reduce the harm caused by
front-end crashes.
A vehicle ahead is indicated by a
control indicator A.
If a vehicle directly ahead is
approached too quickly, a warning
chime and alert in the Driver
Information Centre (DIC) is provided.
A precondition is that forward collision
alert is activated in the vehicle
personalisation menu 3 131 or that it
is not deactivated by pressing V
(depending on the system, see
following).
Depending on the vehicle's
equipment, there are two variants of
the forward collision alert available:
■ Forward collision alert based on
radar system

190Driving and operating
on vehicles equipped with adaptivecruise control 3 182.
■ Forward collision alert based on
front camera system
on vehicles with traditional cruise control or none 3 179.
Forward collision alert based on
radar system The system uses the radar sensor
behind the radiator grille to detect a
vehicle directly ahead, in your path,
within a maximum distance of
150 metres.
Activation
Forward collision alert operates
automatically above walking speed,
provided that Auto collision
preparation setting is not deactivated
in the vehicle personalisation menu
3 131.
Selecting the alert sensitivity
The alert sensitivity can be set to
near, medium or far.
Press E; the current setting is shown
in the DIC. Press E again to change
the alert sensitivity. The setting is also
displayed in the top line of the DIC.
Note that the alert timing sensitivity
setting is shared with the following distance setting of the adaptive cruise control. So changing the alert timing
sensitivity changes the adaptive
cruise control following distance
setting.
Alerting the driver
A green illuminated vehicle ahead
control indicator A illuminates in the
instrument cluster when the system has detected a vehicle in the driving
path. When the distance to a
preceding moving vehicle gets too
small or when approaching another

192Driving and operating
Deactivation
The system can be deactivated.
Press V repeatedly until the following
message appears in the DIC.
General information for both
variants of forward collision alert
9 Warning
Forward collision alert is just a
warning system and does not
apply the brakes. When
approaching a vehicle ahead too
rapidly, it may not provide you
enough time to avoid a collision.
The driver accepts full
responsibility for the appropriate
following distance based on traffic, weather and visibility conditions.
The complete attention of the
driver is always required while
driving. The driver must always be
ready to take action and apply the
brakes.
System limitations
The system is designed to warn only for vehicles, but may react also to
other metallic objects.
In the following cases, forward
collision alert may not detect a vehicle ahead or sensor performance is
limited:
■ on winding roads
■ when weather limits visibility, e.g. fog, rain, or snow
■ when the sensor is blocked by snow, ice, slush, mud, dirt, or
windscreen damage
Following distance
indication
The following distance indication
displays the distance to a preceding
moving vehicle. The system uses,
depending on the vehicle equipment,
either the radar behind the radiator
grille or the front camera in the
windscreen to detect the distance of
a vehicle directly ahead in your lane.
It is active at speeds above 25 mph.
When a preceding vehicle is detected ahead, the distance is indicated inseconds, displayed on a page in the
Driver Information Centre (DIC)
3 118 . Press MENU on the turn signal
lever to select Vehicle Information
Menu X and turn the adjuster
wheel to choose following distance
indication page.

Driving and operating193
The minimum indicated distance is
0.5 s.
If there is no vehicle ahead or the vehicle ahead is out of range, two
dashes will be displayed: -.- s.
Active Emergency Braking Active emergency braking can help to reduce the damage from crashes with vehicles and obstacles directly
ahead, when a collision can no longer be avoided either by manual braking
or by steering. Before the active
emergency braking applies, the driver
is warned by the forward collision
alert 3 189.
The feature uses various inputs (e.g.
radar sensor, brake pressure, vehicle speed) to calculate the probability ofa frontal collision.
Active emergency braking operates automatically above walking speed,
provided that Auto collision
preparation setting is not deactivated
in the vehicle personalisation menu 3 131.
The system includes: ■ brake preparation system
■ emergency automatic braking
■ forward looking brake assist9 Warning
This system is not intended to
replace the driver responsibility of driving the vehicle and looking
ahead. Its function is limited to
supplemental use only. The driver
shall continue to apply the brake
pedal as the driving situation
dictates.
Brake preparation system
When approaching a vehicle ahead
so quickly that a collision is likely, the brake preparation system slightly
pressurises the brakes. This reduces
the response time, when a manual or automatic braking is requested.
The brake system is prepared so that braking can occur more rapidly.
Emergency automatic braking After the brake preparation and just
before the imminent collision, this
function automatically applies limited
braking to reduce the impact speed of
the collision.
Forward looking brake assist
In addition to brake preparation
system and emergency automatic
braking, the forward looking brake
assist function makes the brake assist more sensitive. In this way,
depressing the brake pedal slightly