2018 VOLVO XC90 T8 brakes

DRIVER SUPPORT
* Option/accessory.
272
Driver support systems
The vehicle is equipped with a number of driver support systems that can provide the driver withactive or passive assistance in various situations.
The system can, for example, help the driver maintain a set speed or a set time interval to thevehicle ahead, help prevent a collision by warningthe driver and applying the brakes, or assist thedriver while parking. Some of the systems are standard and others are options. This also varies from market to market.
Related information
• Speed-dependent steering wheel resistance(p. 272)
• Electronic Stability Control (p. 274)
• Stability system Roll Stability Control(p. 273)
• Rear Collision Warning (p. 347)
• Speed limiter (p. 278)
• Cruise control (p. 286)
• Distance Alert
* (p. 291)
• Adaptive Cruise Control
* (p. 295)
• Pilot Assist (p. 311)
• Radar sensor (p. 326)
• Camera (p. 331)
• City Safety
™ (p. 335)
• BLIS
* (p. 348) •
Cross Traffic Alert
* (p. 353)
• Road Sign Information
* (p. 357)
• Driver Alert Control (p. 362)
• Lane Keeping Aid (p. 364)
• Steering assistance at risk of collision(p. 372)
• Park Assist
* (p. 381)
• Park Assist Camera
* (p. 386)
• Park Assist Pilot
* (p. 395)
Speed-dependent steering wheelresistance
Speed-dependent power steering increases the steering wheel resistance in pace with the vehi-cle's speed to give the driver an enhanced feel-ing of control and stability.
Steering may feel stiffer on highways. When parking and at low speeds, it will be easier tomove the steering wheel.
NOTE
In some situations, the power steering may become too hot and require temporary cool-ing – during such time the power steering willwork at reduced output and the steeringwheel may feel more difficult to move. In parallel with the temporarily reduced steer- ing assistance, the driver display shows amessage as well as a STEERING WHEELsymbol.

DRIVER SUPPORT
* Option/accessory.273
WARNING
While the power steering is working at reduced power, the driver support functionswith steering assistance are not available. In such a situation, the driver display shows the
Power steering failure or Power
Steering Assist Temporarily Reduced
message, combined with a STEERING WHEEL symbol.
Changing the level of steering wheel resistance *
To change the level of steering wheel resistance, see the description of the INDIVIDUAL optionunder "Available drive modes" in the "Drivemodes" section. On models not equipped with drive mode con- trols and the INDIVIDUAL option, steering wheelresistance can instead be set in the center dis-play's Top view under:
SettingsMy CarDrive ModesSteering force
Steering wheel resistance settings cannot be accessed when turning at speeds above10 km/h (6 mph).
Related information
•Drive modes (p. 445)
• Pilot Assist (p. 311) •
Lane Keeping Aid (p. 364)
• Steering assistance at risk of collision(p. 372)
• Park Assist Pilot
* (p. 395)
Stability system Roll StabilityControl
The Roll Stability Control (RSC 1
) system helps
minimize the risk of a rollover in the event of e.g. a sudden evasive maneuver or if the vehiclebegins to skid.
The RSC system monitors the lateral angle at which the vehicle is leaning and registers anychanges. Using this information, the system cal-culates the likelihood of a rollover. If there is animminent risk of a rollover, Electronic StabilityControl is activated, engine torque is reduced andbrakes are applied to one or more of the wheelsuntil the vehicle has regained stability.
WARNING
The vehicle

DRIVER SUPPORT
* Option/accessory.
274
Electronic Stability Control
The Electronic Stability Control (ESC 2
) function
helps the driver avoid skidding and improves the vehicle's directional stability.
This symbol will be displayed in the instrument panel when theESC system is intervening. When the ESC has intervened to apply the brakes, a pulsingsound may be heard and the
vehicle may accelerate more slowly than expec-ted when the accelerator pedal is depressed.
The ESC system consists of the following sub- functions: • Stability control 3
• Spin control and active yaw control
• Engine drag control
• Trailer Stability Assist
WARNING
•The Electronic Stability Control system ESC is supplementary driver supportintended to facilitate driving and make itsafer – it cannot handle all situations inall traffic, weather and road conditions.
• ESC is not a substitute for the driver'sattention and judgment. The driver isalways responsible for ensuring the vehi-cle is driven in a safe manner, at theappropriate speed, with an appropriatedistance to other vehicles, and in accord-ance with current traffic rules and regula-tions.
Stability control 3This function helps control the driving and brak-ing force of each individual wheel in an attemptto stabilize the vehicle.
Spin control and active yaw controlThis function is active at low speeds and brakesthe wheels that are spinning to transfer additionalpower from wheels that are not spinning. This function also helps prevent the wheels from spinning while the vehicle is accelerating.
Engine drag control
Engine drag control (EDC
4
) helps prevent inad-
vertent wheel lock, e.g. after downshifting orusing engine braking when driving at low speedson a slippery surface. Inadvertent wheel lock while driving could impair the driver's ability to steer the vehicle.
Trailer Stability Assist *5
Trailer Stability Assist (TSA
6
) is designed to help
stabilize a vehicle that is towing a trailer if thevehicle and trailer have begun to sway. For moreinformation, see "Trailer Stability Assist".
NOTE
The TSA function is deactivated if ESC Sport
Mode is activated.
Related information
• Electronic Stability Control Sport mode (p. 275)
• Activating/deactivating Sport mode in Elec-tronic Stability Control (p. 275)
1
Roll Stability Control
2 Electronic Stability Control
3 Also called traction control.
4 Engine Drag Control
5Trailer Stability Assist is included if the vehicle is equipped with a Volvo original towbar.6
Trailer Stability Assist

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Electronic Stability Control symbolsand messages
A number of symbols and messages related to Electronic Stability Control (ESC) may be dis-played in the instrument panel.
Some examples of symbols and messages are shown in the table below.
SymbolMessageMeaning
Steady glow for approx. 2 seconds. System check when the engine is started.
Flashing light. The ESC is actively operating.
Steady glow. Sport mode is activated.
Note: The ESC system is not deactivated in this mode, but has partially reduced functionality.
ESC Temporarily offThe ESC system's functionality has been temporarily reduced due to high brake system temperatures. The function will be automatically reactivated when the brakes have cooled. See the message in the instrument panel.
ESC Service requiredThe ESC system is not functioning properly.
• Stop the vehicle in a safe place, turn off the engine and then restart it.
• Consult a workshop if the message persists
‒ an authorized Volvo workshop is recommended.
A text message can be erased by briefly pressing the
button in the center of the right-side
steering wheel keypad. If the message persists: Contact a workshop
‒ an
authorized Volvo workshop is recommended.
Related information
• Electronic Stability Control (p. 274)

DRIVER SUPPORT
288
Managing Cruise Control speedCruise Control (CC 29
) can be set to various
speeds.
Setting/changing set speed
Note: This illustration is general and details may vary depending on model.
For vehicles with only CC
–Change a set speed by pressing the (1)
or
(3) buttons briefly or by pressing and
holding them:
• Press briefly
: Press briefly: each press
changes the speed in +/- 1 mph (+/- 1 km/h) increments.
• Press
and hold: Release the button when
the set speed indicator (4) has moved tothe desired speed. •
The most recently set speed will be stored.
If speed is increased by depressing the accelera- tor pedal while pressing the
(1) button on
the steering wheel, the vehicle's speed when the button is pressed will be stored as the set speed. Temporarily increasing speed using the accelera- tor pedal, e.g. when passing another vehicle, willnot affect the setting. The vehicle will return tothe set speed when the accelerator pedal isreleased.
For vehicles with both CC and ACC
–Change a set speed by pressing the (1)
or
(3) buttons briefly or by pressing and
holding them:
• Press briefly
: Press briefly: each press
changes the speed in +/- 5 mph (+/- 5 km/h) increments.
• Press
and hold: Release the button when
the set speed indicator (4) has moved tothe desired speed.
• The most recently set speed will be stored.
If speed is increased by depressing the accelera- tor pedal while pressing the
(1) button on
the steering wheel, the vehicle's speed when the button is pressed will be stored as the set speed. Temporarily increasing speed using the accelera- tor pedal, e.g. when passing another vehicle, will not affect the setting. The vehicle will return tothe set speed when the accelerator pedal isreleased.
Using engine braking instead of
applying the brakes
Cruise Control regulates speed by lightly applyingthe brakes. On downgrades, it can sometimes bedesirable to roll a bit faster and let speed bereduced instead by engine braking alone. Thedriver can temporarily disengage the Cruise Con-trol braking function. To disengage CC:
–Press the accelerator pedal about halfway down and then release it.
> Cruise Control will automatically disen- gage the automatic brake function and speed will only be reduced using theengine braking function.
How drive mode affects cruise controlThe way the cruise control maintains the vehicle'sspeed can vary depending on the selected drive mode 30
.
29 Cruise Control
30 For more information, see "Drive modes".

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Cruise Control Eco Cruise
In the ECO drive mode, cruise control's accelera- tion and deceleration will be smoother than inother drive modes to help provide optimal fuelefficiency and reduced environmental impact.Because of this, the vehicle's actual speed maybe slightly above or below the set speed.
Cruise Control Dynamic Cruise
With the Dynamic drive mode, cruise control's acceleration and deceleration will be faster andmore immediate than in other drive modes.
Related information
•Cruise control (p. 286)
Deactivating and putting CruiseControl in standby mode
Cruise Control (CC 31
) can be temporarily put
into standby mode and then reactivated.
Deactivating and putting Cruise Control in standby mode
Note: This illustration is general and details may vary depending on model.
To put Cruise Control in standby mode:
–Press the button on the steering wheel
(2).
> The Cruise Control markings and symbols will change from WHITE to GRAY, indicat- ing that Cruise Control is temporarilydeactivated and the driver needs to con-trol the vehicle's speed.
Standby mode due to action by the driver
Cruise Control will be temporarily deactivated and put in standby mode if:
• the brakes are applied
• the gear selector is moved to
N
• the vehicle is driven faster than the setspeed for more than 1 minute
The driver must then control the vehicle's speed. Temporarily increasing speed using the accelera- tor pedal, e.g. when passing another vehicle, willnot affect the setting. The vehicle will return tothe set speed when the accelerator pedal isreleased.
Automatic standby mode
Cruise Control will be temporarily deactivated and put in standby mode if:
• the wheels lose traction
• the engine speed (rpm) is too low/high
• the temperature in the brake systembecomes too high
• the vehicle's speed goes below 30 km/h(20 mph).
The driver must then control the vehicle's speed.
Related information
• Cruise control (p. 286)
31
Cruise Control

||
DRIVER SUPPORT
296
WARNING
•The Adaptive Cruise Control function is supplementary driver support intended tofacilitate driving and help make it safer –it cannot handle all situations in all traffic,weather and road conditions.
• The driver is advised to read all sectionsin the Owner's Manual about this functionto learn of its limitations, which the drivermust be aware of before using the func-tion (see the link list at the end of thisarticle).
• Adaptive Cruise Control is not a substi-tute for the driver's attention and judg-ment. The driver is always responsible forensuring the vehicle is driven in a safemanner, at the appropriate speed, with anappropriate distance to other vehicles,and in accordance with current trafficrules and regulations.
NOTE
Depending on market, this function may be either Standard or Optional.
Adaptive Cruise Control regulates speed by accelerating and braking. It is normal for the brakes to emit a slight sound when they arebeing used to adjust speed. Adaptive Cruise Control always attempts to regu- late speed smoothly. The driver must apply thebrakes in situations requiring immediate braking.For example, when there are great differences inspeed between vehicles or if the vehicle aheadbrakes suddenly. Due to limitations in the radarsensor, braking may occur unexpectedly or not atall. Adaptive Cruise Control is designed to follow a vehicle ahead in the same lane and maintain atime interval to that vehicle set by the driver. If theradar sensor does not detect a vehicle ahead, itwill instead maintain the speed set by the driver.This will also happen if the speed of the vehicleahead exceeds the set speed for your vehicle.
• Adaptive Cruise Control can follow anothervehicle at speeds from a standstill up to200 km/h (125 mph).
WARNING
• Adaptive Cruise Control is not a collision avoidance system. The driver is alwaysresponsible and must intervene if the sys-tem fails to detect a vehicle ahead.
• Adaptive Cruise Control does not brakefor people or animals and does not brakefor small vehicles, such as bikes andmotorcycles. Similarly, it does not brakefor low trailers, oncoming, slow-moving orstationary vehicles and objects.
• Do not use Adaptive Cruise Control indemanding situations, such as in city traf-fic, at intersections, on slippery surfaces,with a lot of water or slush on the road, inheavy rain/snow, in poor visibility, onwinding roads, or on on/off ramps.
CAUTION
Maintenance of Adaptive Cruise Control com- ponents may only be performed by a work-shop – an authorized Volvo workshop is rec-ommended.
41
Adaptive Cruise Control
42 Note: This illustration is general and details may vary depending on model.

DRIVER SUPPORT
* Option/accessory.
298 •
Managing Adaptive Cruise Control speed (p. 300)
• Setting Adaptive Cruise Control time inter-vals (p. 301)
• Deactivating/reactivating Adaptive CruiseControl (p. 302)
• Passing assistance with Adaptive CruiseControl (p. 304)
• Starting passing assistance with AdaptiveCruise Control (p. 304)
• Limitations of passing assistance with Adap-tive Cruise Control (p. 305)
• Switching target vehicles with AdaptiveCruise Control (p. 305)
• Automatic braking with Adaptive Cruise Con-trol (p. 306)
• Adaptive Cruise Control limitations (p. 307)
• Switching between Cruise Control and Adap-tive Cruise Control (p. 307)
• Symbols and messages for Adaptive CruiseControl (p. 309)
Adaptive Cruise Control andcollision warning
Collision warning light on the windshield 43
.
Adaptive Cruise Control utilizes approx. 40% of the vehicle's braking capacity. If a situationrequires more braking force than the AdaptiveCruise Control can provide, and if the driver doesnot apply the brakes, a warning light and audiblewarning signal will be activated to alert the driverthat immediate action is required.
NOTE
Visual warnings on the windshield may be dif- ficult to notice in cases of strong sunlight,reflections, extreme light contrasts, or if thedriver is wearing sunglasses or is not lookingstraight ahead.
WARNING
Adaptive Cruise Control only issues a warning for vehicles detected by its radar unit – thus, awarning may come after a delay or not at all.
• Never wait for a warning. Apply the brakes when necessary.
Related information
•
Adaptive Cruise Control
* (p. 295)
43
Note: This illustration is general and details may vary depending on model.