2004 JAGUAR XJ Owners Manual

4-50 On the Road
Caution:
1. RESUME should only be used if the driver is aware of the set speed
and intends to return to it.
2. It is not recommended to resume set speed when a low gear is
selected as ex cessive engine
speeds will occur.
Cruise Control Will Switch Off
and Clear the Memory When:
• The ignition is switched to position ‘0’.
• A fault occurs. The cruise control system will switch OFF and cannot be
used until the fault is cleared.
Cruise Control Automatic
Switch Off
Cruise control will switch off but the set
speed will remain in the memory when:
• The CANCEL button is pressed.
• The brake pedal is pressed.
• The parkbrake is applied.
• Speed falls below 16 mph (26 km/h).
• Neutral, Park or Reverse gear positions are selected.
• DSC is operating.
• The difference between the actual and set speed is too great.
• When the vehicle reaches a maximum
speed of 144 mph (230 km/h).
• The accelerator pedal is used to accelerate beyond the set speed for
too long a period.

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Adaptive Cruise Control (ACC)
(Where fitted)
The adaptive cruise control system is designed to aid the driver
to maintain a gap from the vehicle ahead or a set road speed if
there is no slower vehicle ahead. The system is intended to
provide enhanced operation of th e vehicle when following other
vehicles which are in the same lane and travelling in the same
direction.
!WARNING:
Adaptive cruise control is not a collision warning or
avoidance system. Additionally , adaptive cruise control
will not detect:
1. Stationary or slow moving vehicles below 6 mph (10 km/h).
2. Pedestrians or objects in the roadway.
3. Oncoming vehicles in the same lane. The adaptive cruise control system is based on the use of a radar
sensor which projects a beam directly forward of the vehicle so
as to detect objects ahead. Th e radar sensor is mounted behind
a cover on the left-hand side of the lower cooling aperture,
to provide a clear ‘view’ forward for the radar beam.
• Only use adaptive cruise control when conditions are favourable, that is, straight, dry, open roads with light traffic.
• Do not use in poor visibility, specifically fog, heavy rain,
spray or snow.
• Do not use on icy or slippery roads.

4-52 On the Road
• It is the drivers responsibility to stay alert, drive safely and be in control of
the vehicle at all times.
• Keep the front of the vehicle free from dirt, metal badges or objects,
including vehicle front protectors,
which may prevent the sensor from
operating.
• Do not use ACC when entering or leaving a motorway.
The system is operated by switches
mounted on the steering wheel.
The driver can also intervene at any time
by use of the brake or accelerator pedals.
The steering wheel switches operate as
follows:
(A ) – RESUME: Resume set speed.
( B )– SET+ or SET–: Setthe speed(+) or
increase (+) or decrease (–) the set speed.
( C ) – CANCEL: Cancels without erasing
memorised speed.
( D ) – Gap increase or decrease. Setting a speed
Accelerate as normal
until the required
speed is reached.
Press the SET + butto n briefly and the
vehicle speed will then be stored in the
memory and the system engaged. The set
speed will be displayed on the message
centre.
Entering the follow mode
!WARNING:
When in follow mode the vehicle will
not decelerate automatically to a
stop, nor will the vehicle always
decelerate quickly enough to avoid a
collision without driver intervention.
Once a set speed has been selected,
the driver can release the accelerator and
the set road speed will be maintained.
SETSPEED 50 MPH

On the Road 4 - 53
When a vehicle ahead enters the same
lane or a slower vehicle is ahead in the
same lane, the vehicle speed will be
adjusted automatically until the gap to
the vehicle ahead corresponds to the
preset gap. The vehicle is now in ‘follow
mode’.The warning light in the
instrument cluster will be
illuminated,
and the message centre
will display the gap set.
The vehicle will then maintain the
constant time gap to the vehicle ahead
until:
• The vehicle ahead accelerates to a speed above the set speed.
• The vehicle ahead moves out of lane or out of view.
• The vehicle ahead slows so that ‘low speed automatic switch off’ occurs.
• A new gap distance is set.
If necessary, the vehicle brakes will be
automatically applied to slow the vehicle
to maintain the gap to the vehicle in
front. The maximum braking which is applied
by the ACC system is limited and can be
overridden by the driver applying the
brakes, if required.
Note:
Driver braking will cancel adaptive
cruise control.
If the ACC system predicts that its
maximum braking level will not be
sufficient, then an audible warning will
sound while the ACC continues to brake.
This is accompanied by a red warning
light and ‘DRIVER INTERVENE’ will be
displayed on the message centre.
The driver should take IMMEDIATE
action.
When in follow mode the vehicle will
automatically return to the set speed
when the road ahead is clear, for instance
when:
• The vehicle in front accelerates or changes lane.
• The driver changes lane to either side or enters an exit lane.
The driver should intervene if
appropriate.
Low speed automatic switch off
If the speed of the vehicle decreases
below 18 mph (30 km/h), the ACC system
will be automatically switched OFF and
the instrument warning lamp will go out. If the brakes were
being applied by the
ACC system, they will be slowly released.
This will be accompanied by an audible
warning, a red warning light and ‘DRIVER
INTERVENE’ will be displayed on the
message centre. The driver must take
control.
Overriding the set speed/follow mode
!WARNING:
Whenever the driver is overriding the
ACC by depressing the accelerator
pedal, the ACC will not automatically
apply the brakes to maintain
separation from any vehicle ahead.
The set speed and gap can be overridden
by pressing the accelerator pedal when
cruising at constant speed or in follow
mode. If the vehicle is in follow mode,
the instrument warning lamp will go out
when the ACC is overridden by the driver
using the accelera tor and ‘CRUISE
OVERRIDE’ will be displayed on the
message centre. When the accelerator is
released the ACC function will operate
again and vehicle speed will decrease to
the set speed, or a lower speed if follow
mode is active.
GAP

4-54 On the Road
Changing the set speed
There are three ways to change the set
speed:
1. Accelerate or brake to the required speed and press the ‘SET +’ button.
2. Increase or decrease the speed by pressing and holding either the
‘SET +’ or ‘–’ button until the required
set speed is shown on the message
centre. The vehicle speed will
gradually change to the selected
speed.
3. Increase or decrease the speed in steps of 1 mph (2 km/h) by briefly
pressing the ‘SET +’ or ‘–’ button.
ACC operates between approximately
20 mph and 110 mph (34 km/h and
180 km/h) dependent on the country
specification.
Set speeds outside this range will not be
captured.
The ACC may apply the brakes to slow
down the vehicle to the new set speed.
The new set speed will be displayed on
the message centre for four seconds after
it has been changed. Changing the gap
The gap from the vehicle ahead can be
decreased or increased by pressing the
gap setting rocker switch on the steering
wheel. Four gaps are available and the
selected gap setting will be displayed on
the message centre when the rocker
switch is pressed. After the ignition is
switched ON the default gap will be
automatically selected ready for ACC
operation.
Note:
It is the driver’s responsibility to
select a gap appropriate to the driving
conditions, and in accordance with
national driving regulations.
ACC automatic switch off
Adaptive cruise control will disengage,
but not clear the memory when:
• The CANCEL button is pressed.
• The brake pedal is pressed.
• The vehicle speed falls below 18 mph (30 km/h).
• Neutral, Park or Reverse gear positions are selected.
• The parkbrake is applied.
• DSC is activated. Adaptive cruise control will disengage,
and clear the memory when:
• The ignition switch is set to
position ‘0’.
• Maximum vehicle speed is reached.
• A fault occurs in the ACC system.
Resuming the set speed/follow mode
By pressing the RESUME button after ACC
has been cancelled, for example, after
braking, the ACC will become active
again provided that the set speed
memory has not been erased. The set
speed will be displayed for four seconds
and the original set speed will be
resumed, unless a vehicle ahead causes
the follow mode to become active.
Caution: ‘RESUME’ should only be
used if the driver is aware of the set
speed and intends to return to it.

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Forward alert
Limited detection and warning of objects
ahead is provided during ACC operation
by the ACC ‘DRIVER INTERVENE’
warning.
The forward alert feature additionally
provides warnings whilst ACC is not
engaged, if an object is detected close
ahead then a warning tone and message
will be issued. The brakes will not be
applied.
This additional feature may be switched
on or off using the forward alert switch in
the lower outboard knee bolster
switchpack. When the indicator lamp in
the switch is on, forward alert is active.The sensitivity of the warning may be
changed:
• Pressing the gap decrease button
when ACC is disengaged displays and
then decreases the sensitivity of the
alert.
• Pressing the gap increase button displays and then increases the
sensitivity of the alert.
Both of these are accompanied by the
FORWARD ALERT message on
the message centre.
ACC failure
If a fault occurs during operation of the
system in cruise or follow modes,
the ACC system will switch OFF and
cannot be used until the fault is cleared.
A red warning light and the message
‘DRIVER INTERVENE’ appear briefly, and
are then replaced by an amber warning
light and the message ‘CRUISE NOT
AVAILABLE’.
If failure of the ACC or any related system
occurs at any other time an amber
warning light will be displayed
accompanied by th e message ‘CRUISE
NOT AVAILABLE’. It will not be possible
to activate the ACC system in any mode. Accumulations of dirt, snow or ice on the
on the sensor or cover may inhibit ACC
operation. Fitting of a vehicle front
protector or metallis
ed badges may also
affect ACC operation.
If this occurs in ACC cruise/follow mode,
the red warning light is displayed,
the audible alarm sounds and the
message ‘DRIVER INTERVENE’ appears
briefly. These warnings are then replaced
by the amber warning light and the
message ‘ACC SENSOR BLOCKED’ is
displayed. The system is no longer active.
Clearing the obstruction allows the
system to return to normal operation.
If the obstruction is present when ACC is
inactive, e.g. on initial starting or with the
ACC system switched off, the amber
warning light will be displayed with the
message ‘ACC SENSOR BLOCKED’.
Tyres other than those recommended
may have different sizes. This can affect
the correct operation of the ACC.

4-56 On the Road
Notes on using adaptive cruise
control
1. Adaptive cruise control operates when the gear selector lever is in
position ‘2’, ‘3’ ‘4’ ‘5’ or ‘D’.
2. When engaged, the accelerator pedal rests in the raised position.
Fully release the pedal to allow
normal ACC operation.
3. When braking is applied by the ACC
the brake pedal will move down and
up as braking is applied or removed.
The vehicle brake lights will be
switched on while braking is applied.
!WARNING:
The driver must not rest a foot under
the brake pedal, as it may become
trapped. Driving with ACC active
The system acts by regulating the speed
of the vehicle using engine control and
the brakes. Gear changes may occur in
response to decelerati
on or acceleration
whilst in ACC.
ACC is not a collision avoidance system,
however, during some situations the
system may provide the driver with an
indication that intervention is required.
An audible alarm will sound,
accompanied by a re d warning light and
the message ‘DRIVER INTERVENE’ if the
ACC detects:
• That using maximum ACC braking only is not sufficient.
• That the vehicle speed has decreased below the minimum for ACC
operation.
• A failure has occurred whilst the system is active.

On the Road 4 - 57
Detection issues can occur:
• When driving on a different line to the vehicle in front (A).
• With vehicles which edge into your lane which can only be
detected once they have moved fully into your lane ( B).
There may be issues with the dete ction of vehicles in front when
going into and coming out of a bend ( C).
In these cases ACC may brake late or unexpectedly. The driver
should stay alert and intervene if necessary.