brakes VOLVO XC90 2015 Owner's Manual

DRIVER SUPPORT
* Option/accessory, for more information, see Introduction.269
Deactivation of the auto-hold brake
function
In certain situations, auto-hold will be deactivated when the vehicle is at a standstill and ACC will gointo standby mode. This means that the brakes will be released and the vehicle can begin to roll. The driver must actively apply the brakes to keep the vehicle at a standstill. This can occur in the following situations: • the driver presses the brake pedal
• the parking brake is set
• the gear selector is moved to the
P, N or R
positions
• the driver puts ACC in standby mode
Automatically setting the parking brakeIn certain situations, the parking brake is set automatically to help keep the vehicle at a stand-still. This occurs if:
• the driver unbuckles the seat belt or opens the door
• ACC has kept the vehicle at a standstill formore than approx. 5 minutes
• the engine is turned off
• the brakes overheat
Related information
•
Adaptive Cruise Control (ACC)
* (p. 252)
• Auto-hold brake function (p. 332)
• Parking brake (p. 335)
Radar sensor
The radar sensor is used by several driver sup- port functions to help detect other vehicles.
The radar sensor is used by the following func- tions:
• Distance Alert
*
• Adaptive Cruise Control
*
• Pilot Assist
*
• City Safety
*
Modification of the radar sensor could make itsuse illegal.
Related information
• Radar sensor - type approval (p. 270)
• Radar sensor limitations (p. 245)

DRIVER SUPPORT
274When triggered, City Safety carries out three steps in the following order: 1.
Collision warning
2. Brake assistance
3. Auto-brake
1: Collision warningThe driver is first alerted to the risk of an immi- nent collision. City Safety can detect pedestrians, cyclists or vehicles that are stationary or that are moving inthe same direction as your vehicle. The driver isalerted by a flashing red warning signal, an audi-ble signal and pulsations in the brake pedal.
2: Brake assistanceIf the risk of a collision increases, brake supportwill be activated. This function increases pressure on the brake pedal if the driver does not apply enough pres-sure to the pedal.
3: Auto-brakeThe brakes will be applied automatically. If the driver has not taken action at this stage and a collision is imminent, auto-braking will be trig-gered. Full braking effect will be used to avoidthe collision if possible or to make the speed atthe point of impact as low as possible. In certain situations, auto-braking may begin with limited effect before full braking is used. If City Safety has prevented a collision, the vehi-cle will be kept at a standstill until the drivertakes action. If the vehicle has slowed to avoidcolliding with the vehicle ahead, your speed willbe reduced to that vehicle's speed. When auto-break is triggered, the seat belt pre- tensioners may also be activated, see the article"Seat belts" for additional information. Auto-braking can be cancelled if the driver presses hard on the accelerator pedal. When City Safety applies the brakes, the brake lights will illuminate. When City Safety is triggered and applies the brakes, a text message will be displayed in theinstrument panel.
WARNING
Warnings will only be provided if there is an imminent risk of a collision taking place. Thedriver should be aware of the system's limita-tions before operating the vehicle. Warnings for pedestrians and cyclists will not be provided if the vehicle's speed is above50 mph (80 km/h). City Safety's auto-brake function can help prevent a collision or reduce the speed atwhich a collision occurs. However, the drivershould always apply the brakes, even if auto-brake is operating. The driver is always responsible for maintain- ing the correct speed and distance in relationto the vehicle ahead. Never wait for a collisionwarning or for City Safety to intervene. City Safety maintenance may only be carried out by a trained and qualified Volvo servicetechnician.
Related information
•
City Safety
™ troubleshooting (p. 280)
• City Safety in crossing traffic (p. 277)
• City Safety limitations (p. 278)
• City Safety symbols and messages (p. 282)
• Detecting cyclists and pedestrians with City Safety (p. 275)
• Rear Collision Warning (RCW) (p. 277)
• City Safety warning level settings (p. 275)

DRIVER SUPPORT
275
City Safety warning level settingsCity Safety is always activated but the function's warning distance can be adjusted.
NOTE
City Safety cannot be turned off and activates automatically each time the engine is started.
Setting a warning level (distance)The distance set for warnings determines the system's responsiveness and sets the distance atwhich visual, audible and tangible (haptic) warn-ings will be triggered. If the driver feels that warnings are given too often, the warning level can be lowered. Thismeans that warnings will be provided later, result-ing in fewer warnings being given. To do so:1. Tap
Settings in the center display's Top
view.
2. Tap
My CarIntelliSafeCity Safety.
3. Choose among
Earlier, Normal or Later.
Begin by choosing
Earlier. If too many warnings
are given, change to Normal.
The setting
Later should only used in exceptional
circumstances, e.g., for a more dynamic driving style.
WARNING
• No automatic system can be guaranteed to function 100% correctly in all situa-tions. For that reason, never test CitySafety by driving toward a person orobject. This could result in serious injuryor death.
• Even if the setting
Earlier has been
selected, warnings may be perceived as being given late, e.g., if the difference inspeed is great or if the vehicle aheadbrakes suddenly.
• City Safety can provide a warning for apotential collision but it can never shortenthe driver's reaction time.
• To help make City Safety as effective as possible, always using the setting
Earlieris recommended.
Related information
•City Safety limitations (p. 278)
• City Safety
™ (p. 273)
• Rear Collision Warning (RCW) (p. 277)
Detecting cyclists and pedestrians with City Safety
City Safety can detect vehicles, cyclists and pedestrians.
VehiclesCity Safety detects most types of vehicles that are either stationary, moving in the same direc-tion as your vehicle or approaching when you areabout to turn left. In order for City Safety to detect a vehicle in darkness, its headlights and taillights must be onand clearly visible.
Cyclists
Optimal example of what the system considers to be a cyclist: clear body/bike contours
To help function optimally, City Safety's function for cyclist detection needs clear informationabout the bike itself and the rider's head, arms,

DRIVER SUPPORT
277
City Safety in crossing traffic
City Safety can help the driver when making a left turn in an intersection.
Turning at an intersection
1. The area in which City Safety can detect an oncoming vehicle
In order for City Safety to detect an approaching vehicle in situations where there is a risk of a col-lision, that vehicle must be within City Safety'srange (the red area in the illustration). The following criteria must also be met:
• your vehicle's speed must be at least 3 mph (4 km/h)
• the approaching vehicle's headlights must beon
WARNING
•
City Safety is a supplementary driving aid and does not function in all driving situa-tions or in all traffic, weather or road con-ditions.
• Warnings and braking for an approachingvehicle will usually come at a very latestage.
• The driver is responsible for maintaining asafe distance and speed. Never wait for awarning or for City Safety to take action.
LimitationsIn certain situations, it may be very difficult for City Safety to help the driver avoid a collision withan approaching vehicle in crossing traffic, forexample:
• on slippery roads when Electronic Stability Control is active
• if the approaching vehicle is detected at alate stage
• If the approaching vehicle is partiallyobscured by another vehicle
• if the approaching vehicle moves erratically(e.g., sudden lane changes at a late stage)
Related information
•
City Safety
™ (p. 273)
• City Safety limitations (p. 278)
Rear Collision Warning (RCW)
The
Rear Collision Warning with braking at
standstill (RCW) function can help the driver
avoid rear-end collisions.
RCW is activated automatically each time the engine is started and cannot be turned off. RCW can warn the driver of a vehicle approach- ing yours from behind by rapidly flashing yourrear turn signals. RCW is only activated when a vehicle is rapidly approaching your vehicle from behind. At speeds below 20 mph (30 km/h), if RCW determines that your vehicle is at risk of a rear-end collision, the front seat belt pretensionersand the Whiplash Protection System are acti-vated. Just prior to the collision, the brakes are also applied to help reduce your vehicle's forwardmovement if and when the collision occurs. How-ever, this can only happen if your vehicle is sta-tionary. The brakes will be released immediately if the accelerator pedal is pressed.

DRIVER SUPPORT
278
NOTE
•Due to local traffic regulations in certain markets, RCW will
not activate the rear
turn signals. That part of the function will be deactivated.
• The use of the rear turn signals will alsobe deactivated if the City Safety warning level is set at
Later. See also the section
"Setting a warning level (distance)" in the article "City Safety settings."
• If RCW detects a vehicle approachingfrom behind, the seat belt pretensionersand Whiplash Protection System will beactivated.
LimitationsIn some circumstances, it may be difficult for RCW to help the driver if there is a risk of a colli-sion, such as: •
In slippery conditions when Electronic Stability Control is active
• If the vehicle approaching from the rear isdetected at a late stage
• If the vehicle approaching from the rearchanges lanes at a late stage
• If the vehicle approaching from the rear ismoving at a speed above approx. 50 mph(80 km/h) detected at a late stage
Related information
•
City Safety
™ (p. 273)
• Whiplash protection system (p. 89)
• Seat belts (p. 58)
• City Safety warning level settings (p. 275)
City Safety limitations
City Safety ™ may have limited or reduced func-
tionality in certain situations.
The function has several limitations that the driver should be familiar with:
Low objectsHanging objects, such as flags for overhanging loads or accessories such as auxiliary lights orfront protective grids that extend beyond theheight of the hood may limit City Safety's func-tion.
Slippery driving conditionsThe extended braking distance on slippery roads may reduce City Safety's capacity to help avoid acollision. In situations of this type, the ABSbrakes and Electronic Stability Control will helpprovide braking power and stability.
BacklightingStrong sunlight, reflections, extreme light con- trasts, the use of sunglasses, or if the driver is notlooking straight ahead may make the visual warn-ing signal in the windshield difficult to see.

DRIVER SUPPORT
282
City Safety symbols and messages
A number of City Safety-related messages may be displayed in the instrument panel.
SymbolMessageExplanation
City Safety City Safety was activatedWhen City Safety is braking or has applied the brakes, one of more symbols may illuminate in the instrument panel and a text message will be displayed.
City Safety Reduced functionality Service requiredThe system is not functioning properly. Contact a trained and authorized Volvo service technician.
Related information
• City Safety
™ (p. 273)

DRIVER SUPPORT
* Option/accessory, for more information, see Introduction.
294
Park Assist limitations
The Park Assist system has certain limitations.
NOTE
A trailer hitch whose wiring is integrated with the vehicle's electrical system will be includedin the measurement of the available spacebehind the vehicle.
NOTE
• The system will not detect high objects, such as a loading dock, etc.
• Objects such as chains, thin shiny polesor low objects may temporarily not bedetected by the system. This may resultin the pulsing tone unexpectedly stoppinginstead of changing to a constant tone asthe vehicle approaches the object. Insuch cases, use caution when backing upor stop the vehicle to help avoid damage.
• In certain circumstances, the park assistsystem may give unexpected warning sig-nals that can be caused by externalsound sources that use the same ultra-sound frequencies as the system. Thismay include such things as the horns ofother vehicles, wet tires on asphalt, pneu-matic brakes, motorcycle exhaust pipes,etc. This does not indicate a fault in thesystem.
Cleaning the sensors
Location of the Park Assist sensors
The sensors must be cleaned regularly to ensure that they work properly. Clean them with waterand a suitable car washing detergent.
NOTE
If the sensors are obstructed by e.g., dirt, snow, or ice, this could result in false warningsignals from the park assist system.
Related information
•
Park Assist
* (p. 292)
• Activating/deactivating Park Assist (p. 293)
• Park assist symbols and messages (p. 295)

DRIVER SUPPORT
* Option/accessory, for more information, see Introduction.301
•
With
360° view selected, objects/obstacles
may not be detected at the edges of the indi- vidual cameras' fields of vision.
• A crossed-out camera icon means that thecamera is not functioning properly.
Ambient lightingThe camera images are adjusted automatically to the ambient light, which means the image mayvary slightly in terms of light and quality. Poorambient lighting may reduce the quality of theimage.
Maintenance
• Keep the camera's lens free of dirt, ice and snow. This is particularly important in poorambient lighting conditions.
• Remove dirt, ice and snow carefully to avoidscratching the lenses.
• Clean the lens regularly with warm water anda suitable car washing detergent.
Related information
•
Park Assist Camera (PAC)
* (p. 296)
Park Assist Pilot (PAP) *
Park Assist Pilot (PAP) helps the driver drive into and leave parking spaces.
Park Assist Pilot (PAP) provides assistance when parking by measuring the parking space andturning the steering wheel to guide the vehicleinto the space. Information about the actions required by the driver is provided in the center display in the formof symbols, images and text.
NOTE
The driver's task is to follow the instructions, select a gear ( D or R), regulate the vehicle's
speed, apply the brakes when necessary and stop.
Types of parking
Parallel parking
Procedure for parallel parking
PAP helps park the vehicle as follows:
1. The system searches for and measures a possible parking space. While this is being done, the vehicle's speed may not exceedapprox. 20 mph ( 30 km/h). When backinginto a space, the speed may not exceedapprox. 12 mph ( 20 km/h).
2. The vehicle is steered while it is backing into the parking space.
3. The vehicle's position is adjusted in the park- ing space by moving forward and rearward.

DRIVER SUPPORT
* Option/accessory, for more information, see Introduction.305
2. Follow the instructions provided. The proce- dure is the same as when parking the vehicle. The steering wheel may turn back slightly when the function is completed and the driver mayhave to turn the back before leaving the parkingspace. If PAP determines that the driver can leave the parking space without assistance, the functionwill deactivate before the vehicle is completelyout of the space.
Related information
•
Park Assist Pilot (PAP)
* (p. 301)
• Park Assist Pilot (PAP)
* limitations (p. 305)
• Park Assist Pilot (PAP)
* symbols and mes-
sages (p. 307)
Park Assist Pilot (PAP) * limitations
The PAP function may be limited in certain situa- tions.
The PAP parking sequence is cancelledA parking sequence will be cancelled:
• if the vehicle is driven too fast (above approx. 4 mph (7 km/h)
• if the driver taps
Cancel in the center display
• if the driver touches the steering wheel
• if the anti-lock brakes or Electronic Stability Control are activated (e.g., if a wheel beginsto spin or lose traction)
In such cases, a text message will explain why the parking sequence was cancelled.
NOTE
• PAP will not function correctly if its sen- sors are obstructed by dirt, snow, etc.
• In certain situations, PAP may not be ableto measure a parking space. This couldbe due to external sources of sound (e.g.,a vehicle's horn, tires on wet asphalt,pneumatic brakes, noise from a motorcy-cle's exhaust, etc.) emitting ultrasoundusing approximately the same frequen-cies as PAP.
Points to keep in mindPAP is a parking aid only and the driver should always be prepared to take control and cancel aparking sequence. This can be due to one ormore of the following factors:
• PAP's function is based on the way that the vehicles are parked behind and in front ofyour parking space. If they are, for example,parked too close to the curb, there is a riskthat your vehicle's tires or wheel rims couldbe damaged by the curb during the parkingprocedure.
• PAP is intended to provide parking assis-tance on straight streets, not sections ofstreet with curved or irregular curbs. Be surethat your vehicle is parallel to the curb whenPAP measures the parking space.
• PAP may not be able to provide parkingassistance on narrow streets due to lack ofspace to maneuver the vehicle. In situationslike this, it may help to drive as close to theside of the road as possible where the park-ing space is located.
• Use only approved tires with the correct infla-tion pressure because this affects PAP'scapacity to provide parking assistance.Changing to a different approved tire sizemay affect PAP's parameters. Consult atrained and qualified Volvo service technician.
• Heavy rain or snow may inhibit PAP'scapacity to correctly measure a parkingspace.

DRIVER SUPPORT
311
SymbolMessageDescription
ESC Temporarily offThe ESC system function has been temporarily reduced due to high brake disc temperature. The function reac- tivates automatically when the brakes have cooled.
ESC Service requiredThe ESC system is not functioning properly.
• Stop the vehicle in a safe place, turn off the engine and restart it.
• If the message is still displayed when the engine has restarted, drive to an authorized Volvo workshop to have the system inspected.
WARNING
The stability system is intended to help improve driving safety. It supplements, but cannever replace, the driver's judgment andresponsibility when operating the vehicle.Speed and driving style should always beadapted to traffic and road conditions.
Related information
• Electronic Stability Control (ESC) (p. 308)