2017 VOLVO XC90 TWIN ENGINE HYBRID brake sensor

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DRIVER SUPPORT
* Option/accessory, for more information, see Introduction.308

WARNING
Pilot Assist only provides warnings for vehi-cles that its radar sensor and camera havedetected. For this reason, a warning may begiven later than expected or not at all. Thedriver should never wait for a warning beforeapplying the brakes.

Head-up-display *
A flashing symbol alerts the driver
If the vehicle is equipped with a head-up display,a flashing symbol in the windshield will alert thedriver.
NOTE
Strong sunlight, reflections, extreme light con-trasts, the use of sunglasses, or if the driver isnot looking straight ahead may make the vis-ual warning signal in the windshield difficult tosee.

Related information
•Pilot Assist* (p. 295)
•Starting and activating Pilot Assist-2(p. 308)
•Changing Pilot Assist-2 speed (p. 310)
•Setting a Pilot Assist-2 time interval (p. 311)
•Changing target vehicles and automaticbraking with Pilot Assist-2 (p. 314)
•Deactivating/resuming Pilot Assist (p. 312)
•Passing Assistance with Adaptive CruiseControl or Pilot Assist-2 (p. 289)
•Pilot Assist-2 limitations (p. 315)
•Pilot Assist-2 symbols and messages(p. 317)
•Adaptive Cruise Control (ACC)* (p. 281)
•Distance Alert* (p. 279)
•Head-up display (HUD)* (p. 122)
•Radar sensor limitations (p. 319)
•Camera limitations (p. 323)
Starting and activating Pilot Assist-2
Pilot Assist has to be started and then activatedbefore it can provide steering assistance andregulate speed and the distance to the vehicleahead.
Function buttons and symbols

DRIVER SUPPORT
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* Option/accessory, for more information, see Introduction.313
In standby mode, the driver will have to regulatethe vehicle's speed and the distance to the vehi-cle ahead.
When Pilot Assist is in standby mode and yourvehicle comes too close to another vehicle, thedriver will be alerted by the Distance Alert func-tion.

Standby mode due to action by the driver
Pilot Assist is temporarily deactivated and put instandby mode if:
•the brakes are applied
•The gear selector is moved to N
•the turn signals are used for more than1 minute
•the vehicle is driven faster than the setspeed for more than 1 minute.
A temporary increase in speed, such as whenpassing another vehicle, does not affect the PilotAssist set speed. The vehicle will return to the setspeed when the accelerator pedal is released.
When the turn signals are used, Pilot Assist'ssteering function will be temporarily deactivated.When this is no longer the case, the steeringfunction will reactivate if the traffic lane's sidemarker lines can still be detected.

Automatic standby mode
Pilot Assist interacts with other systems, such asElectronic Stability Control. If any of these other
systems are not functioning properly, Pilot Assistwill automatically be deactivated.
WARNING
If this happens, the driver will be alerted by anaudible signal and a message in the instru-ment panel. The driver will have to adapt thevehicle's speed, apply the brakes when nec-essary and keep a safe distance to the vehicleahead.
Pilot Assist switches automatically to standbymode if:
•the vehicle's speed is below approx. 3 mph(5 km/h) and Pilot Assist cannot determine ifa vehicle ahead is a stationary vehicle or anobject.
•the vehicle's speed is below approx. 3 mph(5 km/h) and the vehicle ahead turns so thatPilot Assist no longer has a vehicle to follow(target vehicle).
•the driver's hands are not on the steeringwheel
•the driver's door is opened
•the driver unbuckles the seat belt
•engine speed (rpm) is too high/low
•the wheels lose traction
•brake temperature is too high
•the parking brake is set
•The camera lens/radar sensor is covered bye.g., wet snow or if heavy rain interferes withradar waves

Reactivating Pilot Assist from standby
mode
Generic illustration
–Press the button (1).
>The most recently set speed will be used.

WARNING
There may be a significant increase in speed
after the button has been pressed.

Related information
•Pilot Assist* (p. 295)
•Pilot Assist-2* (p. 305)
•Starting and activating Pilot Assist-2 (p. 308)

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DRIVER SUPPORT
* Option/accessory, for more information, see Introduction.316

WARNING
Pilot Assist is not a collision avoidance sys-tem. The driver is always responsible forsteering or applying the brakes if the systemdoes not detect another vehicle.
Do not use Pilot Assist in demanding drivingconditions such as city driving or other heavytraffic situations, in slippery conditions, whenthere is a great deal of water or slush on theroad, during heavy rain or snow, in poor visibil-ity, on winding roads or on highway on- or off-ramps.
In certain situations, it may be difficult for PilotAssist to assist the driver correctly or to deac-tivate automatically. In such cases, it is advisa-ble not to use Pilot Assist. Examples of suchsituations may be:
•the lane's side market lines are missing,badly faded or cross each other.
•the division of lanes is not clear, e.g.,when a line divides or merges withanother, at exits or if there are many roadsigns/markers.
•there are edges or other lines on or nearthe lane, e.g., curbs, cracks, repairedareas, sharp shadows, etc.
•the lane is narrow or winding.
•the lane is at the top of a hill, on anuneven road surface or over a bump.
•bad weather conditions (rain, snow, fog,slush, poor visibility, backlighting, etc).
The driver should also be aware that PilotAssist has the following limitations:
•High curbs, barriers and temporary obsta-cles (cones, barriers etc) may not bedetected or could be detected incorrectlyas side marker lines, which may create arisk of collision. The driver must ensure asafe distance to these obstacles.
•The camera or radar sensor may not beable to detect objects if there are pot-holes or if there are stationary objectspartially or completely blocking the road.
•Pilot Assist does not "see" pedestrians,animals, etc.
•Pilot Assist's steering capacity is limitedand may not always be able to help thedriver keep the vehicle in the lane.
The driver can always take action to override PilotAssist.

Steep roads and/or heavy loads
Pilot Assist is primarily intended for use on rela-tively level roads. The function may not be able tomaintain the correct time interval to the vehicleahead on when driving down steep hills. Thedriver should be attentive and prepared to applythe brakes in these situations.
Do not use Pilot Assist when the vehicle is trans-porting a heavy load or if it is towing a trailer.
Additional information
•The Off Road drive mode cannot beselected if Pilot Assist is activated.
•Pilot Assist uses the vehicle's camera andradar sensor, which have certain general limi-tations. See the articles "Camera limitations"and "Radar sensor limitations" for additionalinformation.

Related information
•Pilot Assist* (p. 295)
•Pilot Assist-2* (p. 305)
•Starting and activating Pilot Assist-2 (p. 308)
•Changing Pilot Assist-2 speed (p. 310)
•Setting a Pilot Assist-2 time interval (p. 311)
•Changing target vehicles and automaticbraking with Pilot Assist-2 (p. 314)
•Deactivating/resuming Pilot Assist (p. 312)
•Passing Assistance with Adaptive CruiseControl or Pilot Assist-2 (p. 289)
•Pilot Assist-2 symbols and messages(p. 317)
•Radar sensor limitations (p. 319)
•Camera limitations (p. 323)

DRIVER SUPPORT
326
City Safety™
City Safety™ is a support system designed tohelp alert the driver to pedestrians, cyclists, largeanimals and vehicles that may appear suddenlyin front of your vehicle by providing visual, audi-ble and haptic alerts. The vehicle will brake auto-matically if the driver is unable to react quicklyenough.

City Safety introduction
Location of the camera and radar sensor (generic illus-tration)
City Safety can help prevent a collision or lowerthe vehicle's speed at the point of impact.
WARNING
•City Safety™ is a supplemental aid to thedriver. It can never replace the driver

DRIVER SUPPORT
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327

WARNING
Warnings will only be provided if there is animminent risk of a collision taking place. Thedriver should be aware of the system's limita-tions before operating the vehicle.
Warnings and automatic braking for pedes-trians and cyclists are deactivated at speedsabove approx. 43 mph (70 km/h).
City Safety's auto-brake function can helpprevent 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 does not activate the auto-brakefunction during fast acceleration.
City Safety maintenance may only be carriedout by a trained and qualified Volvo servicetechnician.
Function overview
Audio-visual collision warning
Distance monitoring by a camera and radarsensor
When triggered, City Safety carries out threesteps in the following order:
1.Collision warning
2.Brake assistance
3.Auto-brake

1: Collision warning
The driver is first alerted to the risk of an immi-nent collision.
City Safety can detect pedestrians, cyclists orvehicles that are stationary, are moving in thesame direction as your vehicle or are in your vehi-cle's path.
City Safety can also detect pedestrians, large ani-mals or cyclists that are crossing in front of yourvehicle.
If there is a risk of a collision with a pedestrian,cyclist, large animal or a vehicle, as well as vehi-cles described in the article "City Safety in cross-ing traffic," the driver will be alerted by a flashingred warning signal, an audible signal and a hapticwarning in the form of pulsations in the brakepedal. At lower speeds, during hard braking or ifthe accelerator pedal is pressed, the haptic warn-ing will not be given.
2: Brake assistance
If the risk of a collision increases, brake supportwill be activated.
This function increases pressure on the brakepedal if the driver does not apply enough pres-sure to the pedal.

3: Auto-brake
The brakes will be applied automatically.
If the driver has not taken action at this stage anda 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 withlimited effect before full braking is used.
If City Safety has prevented a collision, the vehi-cle will be kept at a standstill until the driver

DRIVER SUPPORT
* Option/accessory, for more information, see Introduction.359

Side park assist
The system's side sensors are activated automat-ically when the engine is started and are active atspeeds below approximately 6 mph (10 km/h).
The distance monitored along the sides of thevehicle is approximately 1 ft (30 cm). The audiblesignal comes from the side speakers.
Front park assist
The system's front sensors are activated auto-matically when the engine is started and areactive at speeds below approximately 6 mph(10 km/h).
The distance monitored in front of the vehicle isapproximately 2.5 ft (80 cm). The audible signalcomes from the front speakers.
Front Park Assist is deactivated if the parkingbrake is applied or if the gear selector is put in P.
When installing auxiliary headlights, be sure thatthey do not obstruct the front sensors. Otherwise,these lights could trigger a Park Assist warning.

Related information
•Activating/deactivating Park Assist (p. 359)
•Park Assist limitations (p. 360)
•Park assist symbols and messages (p. 361)
Activating/deactivating Park Assist
The Park Assist system can be turned on or off.
On/Off
Park Assist's front and side sensors are activatedautomatically when the engine is started. Therear sensors activate if the vehicle rolls rearwardin N or if R is selected.
This function can be activated/deactivated in the center dis-play's Function view.
–Tap the Park Assist button.
>Green indicator: the function is active.Gray indicator: the function is deactivated.

Related information
•Park Assist* (p. 358)
•Park Assist limitations (p. 360)
•Park assist symbols and messages (p. 361)

DRIVER SUPPORT
* Option/accessory, for more information, see Introduction.360
Park Assist limitations
The Park Assist system has certain limitations.

NOTE
A trailer hitch whose wiring is integrated withthe vehicle's electrical system will be takeninto account when measuring the availablespace behind the vehicle.
NOTE
•The system will not detect high objects,such as a loading dock, etc.
•Certain materials or fabrics may not bedetected by the sensors. Objects made ofthese materials or people wearing cloth-ing made of these fabrics may not bedetected.
•Children or animals near the vehicle maynot always be detected.
•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,other vehicles with similar ultrasound sys-tems, etc. This does not indicate a fault inthe system.
Cleaning the sensors
Location of the Park Assist sensors
The sensors must be cleaned regularly to ensurethat 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 or thesystem may not function at all.

Related information
•Park Assist* (p. 358)
•Activating/deactivating Park Assist (p. 359)
•Park assist symbols and messages (p. 361)

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STARTING AND DRIVING
* Option/accessory, for more information, see Introduction.378

Instrument panel symbols
SymbolExplanation
A
B
Red symbol: Check the brake fluidlevel. If the level is low, top up andhave the system inspected todetermine the cause of the loss offluid.
Yellow symbol: there is a fault inthe brake pedal sensor.
A
B
Steady glow for more than2 seconds: there is a fault in theABS system. The normal brakesystem will still function but with-out ABS brake modulation.
If Brake pedalCharacteristicschanged Service required isdisplayed, the Brake-by-Wire sys-tem is not functioning properly.The brake pedal must be pressedfarther down and with more pres-sure for braking effect.
AUS modelsBCanadian models

WARNING
If both symbols illuminate at the same timeand the brake level is below the MIN mark inthe reservoir or if a brake system-related mes-sage is shown in the instrument panel: DONOT DRIVE. Have the vehicle towed to atrained and qualified Volvo service technicianand have the brake system inspected.
If both symbols illuminate at the same timeand the brake level is normal (not below theMIN mark in the reservoir) or if a brake sys-tem-related message is shown in the instru-ment panel: drive the vehicle carefully to anauthorized Volvo workshop and have thebrake system inspected by a trained andqualified Volvo service technician.

Related information
•Brake functions (p. 378)
•Brake assist system (p. 379)
•Emergency brake lights (p. 380)
•General information about the XC90 T8 TwinEngine Plug-in Hybrid (p. 16)
Brake functions
The vehicle's standard braking features are aug-mented by a number of auxiliary help functions.
In addition to the wheel brakes and the parkingbrake, the vehicle is equipped with several auto-matic brake assist functions. These systems helpthe driver by e.g., keeping the vehicle stationarywhen the brake pedal is not depressed (at a traf-fic light or intersection), when starting up a hill orwhen driving down a hill.
These systems include:
•Auto-hold brakes
•Hill Start Assist
•Braking assist after a collision
•Hill Descent Control*

Related information
•Brakes (p. 376)
•Parking brake (p. 382)
•Hill Descent Control (HDC) (p. 380)
•Auto-hold brake function (p. 379)