2015 VOLVO XC70 brake sensor

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Adaptive Cruise Control (ACC)*
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164* Option/accessory, for more information, see Introduction.
• The vehicle ahead must be within a rea- sonable distance (not farther away thanapprox. 100 ft/30 meters)
• The lowest speed that can be selected is18 mph (30 km/h), although ACC will alsohelp maintain the set time interval to thevehicle ahead at lower speeds, includinga complete stop.
During short stops (less than approximately 3 seconds) in slow-moving traffic, your vehi-cle will begin moving again automatically assoon as the vehicle ahead begins to move. If it takes more than 3 seconds for the vehicle ahead to begin moving, ACC will be automat-ically go into standby mode. The driver will then have to reactivate ACC in one of the following ways:
• By pressing
• By accelerating up to at least 3 mph (4 km/h). ACC will then resume followingthe vehicle ahead.
Your vehicle will then resume following the vehicle ahead at the set time interval.
NOTE
ACC can remain active and keep your vehicle at a standstill for up to 4 minutes.After 4 minutes have elapsed, the parkingbrake will be engaged and ACC will go intostandby mode. To reactivate ACC, the driver must release the parking brake (see page 145).
Automatic standby mode when ACC changes target vehicles
If the vehicle ahead turns suddenly, there may be a stationary vehicle ahead
The following only applies at speeds below approximately 18 mph (30 km/h) :
If ACC changes target vehicles (the vehicle that the radar sensor has detected) from amoving vehicle to a stationary one, the sys-tem will apply the brakes in your vehicle.
WARNING
At speeds above 18 mph (30 km/h), ACC
will not react to a stationary vehicle and apply the brakes but will instead acceler-ate to the previously set speed. The drivermust actively apply the brakes to stop thevehicle.
ACC disengages and goes into standby mode if:
• Your vehicle's speed goes below 10 mph (15 km/h) and ACC cannot determine ifthe target object is a stationary vehicle orsome other type of object such as e.g., aspeed bump.
• Your vehicle's speed goes below 10 mph(15 km/h) and the vehicle ahead turns sothat ACC no longer has a target vehicle tofollow.
No automatic braking when at a standstill
In certain situations, ACC will no longer apply the brakes and go into standby mode whilethe vehicle is not moving. This means that thedriver will have to apply the brakes. This happens if:
• The driver presses the brake pedal
• The parking brake is activated

04 Driver support
Adaptive Cruise Control (ACC)*
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* Option/accessory, for more information, see Introduction.165
•
The gear selected is moved to
P,N or R
• The driver presses the
button to put
ACC in standby mode
The parking brake is applied
automatically
In certain situations, ACC will apply the park- ing brake in order to continue keeping thevehicle at a standstill. This happens if:
• The driver opens the door or takes off his/her seat belt
• DSTC is put in Sport mode (seepage 152)
• ACC has kept the vehicle at a standstillfor more than 2 minutes
• The engine has been switched off
• The brakes have overheated
The radar sensor and its limitations
In addition to being used by ACC, the radar sensor is also used by Distance Alert (seepage 169) and Collision Warning with FullAuto-brake and Pedestrian Detection (seepage 178). This sensor is designed to detectcars or larger vehicles driving in the samedirection as your vehicle, in the same lane.
WARNING
• If there is visible damage to the front grille or you suspect that the radarsensor may be damaged in any way,contact a trained and qualified Volvoservice technician as soon as possible.The radar sensor may only functionpartially (or not at all) if it is damagedor is not securely fastened in place.
• Accessories or other objects, such asextra headlights, must not be installedin front of the grille.
• Modification of the radar sensor couldmake its use illegal.
The radar sensor's capacity to detect vehi- cles ahead is impeded:
• if the radar sensor is obstructed and can- not detect other vehicles, for example inheavy rain, or if snow or other objects areobscuring the radar sensor.
NOTE
Keep the area in front of the radar sensor clean.
• if the speed of vehicles ahead is signifi- cantly different from your own speed.
Situations where ACC may not function optimally
WARNING
•The radar sensor has a limited field of vision. In some situations it may detecta vehicle later than expected or notdetect other vehicles at all.
• If ACC is not functioning properly,cruise control will also be disabled.

04 Driver support
Adaptive Cruise Control (ACC)*
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166* Option/accessory, for more information, see Introduction.
Radar sensor's field of vision (shown in pink)
In certain situations, the radar sensor cannot detect vehicles at close quarters,for example a vehicle that suddenlyenters the lane between your vehicle andthe target vehicle.
Small vehicles, such as motorcycles, or vehicles not driving in the center of thelane may remain undetected.
In curves, the radar sensor may detect the wrong vehicle or lose sight of the tar-get vehicle.
WARNING
• Adaptive Cruise Control cannot cover all driving situations and traffic,weather and road conditions. The"Function" section provides informa-tion about limitations that the drivermust be aware of before using thisfeature.
• This system is designed to be a sup-plementary driving aid. It is not, how-ever, intended to replace the driver'sattention and judgement. The driver isresponsible for maintaining a safe dis-tance and speed and must intervene ifAdaptive Cruise Control does notmaintain a suitable speed or suitabledistance to the vehicle ahead.
• Maintenance of ACC components mayonly be performed by a trained andqualified Volvo technician.
WARNING
• Adaptive Cruise Control is not a colli- sion avoidance system. The driver isalways responsible for applying thebrakes if the system does not detectanother vehicle.
• Adaptive Cruise Control does not reactto people or animals, or small vehiclessuch as bicycles and motorcycles. Italso does not react to slow moving,parked or approaching vehicles, orstationary objects.
• Do not use Adaptive Cruise Control indemanding driving conditions such ascity driving or other heavy traffic situa-tions, in slippery conditions, whenthere is a great deal of water or slushon the road, during heavy rain orsnow, in poor visibility, on windingroads or on highway on- or off-ramps.
Fault tracing and actions
If the message Radar blocked See manualis displayed, this means that the radar signals from the sensor have been obstructed andthat a vehicle ahead cannot be detected. This, in turn, means that the functions of the ACC, Distance Alert, and Collision Warning

04 Driver support
Adaptive Cruise Control (ACC)*
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168* Option/accessory, for more information, see Introduction.
SymbolMessageDescription
-Cruise control Cancel- ledACC has been automatically switched off. The driver has to regulate the vehicle’s speed/distance to the vehicle ahead.
-Cruise control Unavail- ableACC cannot be put in active mode. This may be due to: • high brake temperature
• the radar sensor is obstructed (by heavy rain, snow, etc.)
Radar blocked See manualACC has been temporarily disconnected because the radar is obstructed in some way and cannot detect other vehicles. In this situation, the driver can switch to standard cruise control, see page 163See page 165 for information on the radar sensor’s limitations.
-Cruise control Service requiredACC is not functioning. Contact a trained and qualified Volvo service technician.
-Press Brake To hold +
an audible signalThe vehicle is at a standstill and ACC will release the brakes before the parking brake engages to keep the vehicle stopped but a problem with the parking brake means that the vehicle may begin to roll. The driver will have to apply the brakes. The message will remain in the display and the audible signal will continue until the driver applies the brakes or presses the accelerator pedal.
-Below 30 km/h Only followingThis is displayed if you try to activate ACC at speeds below approx. 18 mph (30 km/h) without a vehicle ahead within range (approx. 100 ft/30 meters).

04 Driver support
Distance Alert*
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* Option/accessory, for more information, see Introduction.171
Symbols and text messages
SymbolMessageDescription
Radar blocked See manualDistance Alert has been temporarily disconnected because the radar is obstructed in some way and can- not detect other vehicles. See page 165 for information on the radar sensor’s limitations.
Collision warn. Serv- ice requiredDistance Alert or Collision Warning with Full Auto-brake and Pedestrian Detection is not functioning prop- erly. Contact a trained and qualified Volvo service technician.

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City Safety™
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WARNING
•City Safety™ only reacts to vehicles traveling in the same direction as yourvehicle and does not react to smallvehicles or motorcycles or to people oranimals.
• City Safety™ is not activated whenyour vehicle is backing up.
• City Safety™ functions at speeds upto 30 mph (50 km/h). This system canhelp prevent a collision if the
differ-
ence in speed between your vehicle
and the vehicle ahead is less than9 mph (15 km/h). If the difference inspeed is greater, a collision cannot beavoided but the speed at which thecollision occurs can be reduced. Thedriver must apply the vehicle’s brakesfor full braking effect.
• City Safety™ will not intervene in apotential collision situation if the vehi-cle is being driven actively. The driveris always responsible for maintaining asafe distance to a vehicle or objectahead.
Function
Location of the laser sensor in the windshield 2
City Safety™ monitors traffic ahead of you using a laser sensor mounted in the uppersection of the windshield. If a collision isimminent, City Safety™ will automaticallyapply the brakes, which may feel like hardbraking. If the difference in speed between your vehi- cle and the vehicle ahead is more thanapproximately 9 mph (15 km/h), City Safety™alone cannot prevent a collision from takingplace. The driver must apply the brakes tohelp avoid a collision or reduce its effect. When the function activates and applies the brakes, a message will appear in the informa- tion display to indicate that the system is/hasbeen active.
NOTE
•
When City Safety™ applies the brakes, the brake lights will illuminate.
• In cases where City Safety™ has stop-ped the vehicle, the system will thenrelease the brakes. The driver mustapply the brakes to keep the vehicle ata standstill.
Using City Safety™
NOTE
The City Safety™ function is activated automatically each time the engine hasbeen switched off and restarted.
On and OffIn certain situations, it may be desirable to switch City Safety™ off, such as when drivingin close quarters where leaves, branches, etc.may obscure the hood and windshield. When the engine is running, City Safety™ can be switched off as follows:
2
The illustration is generic; certain details may vary from model to model

04 Driver support
City Safety™
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Maximum pulse energy2.64 μJ
Maximum average output45 mW
Pulse length33 ns
Divergence (horizontal × verti- cal)28° × 12°
NOTE
The function of aftermarket laser detectors may be affected by City Safety's laser sen-sor.
WARNING
The laser sensor emits light when the igni- tion is in mode II or higher, even if City
Safety™ has been switched off.
WARNING
Eye injury may occur if any of the following points are not followed: • It is essential that all pertinent instruc- tions be followed when handling laserinstruments. Testing, repairing, remov-ing, adjusting and/or replacing anycomponents in the laser sensor mayonly be done by a trained and qualifiedVolvo service technician.
• Do not remove the laser sensor(including removal of the lenses). Alaser sensor that has been removedbelongs to laser class 3B according tostandard IEC 60825-1. Devices in laserclass 3B present a risk of injury to theeyes.
• The laser sensor’s connector must bedisconnected before the sensor isremoved from the windshield.
• The laser sensor must be mounted inplace on the windshield before con-necting the sensor’s connector.
• Do not view the laser sensor (whichemits spreading, invisible laser beams)with optical instruments from a dis-tance of less than 4 inches (100 mm).Symbols and messages in the display
When City Safety™ automatically applies the brakes, one or more of the symbols in themain instrument panel may illuminate and itsassociated message will be displayed. A text message can be erased by pressing briefly on the
OK button on the turn signal
lever.

04 Driver support
City Safety™
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SymbolMessageMeaning/action required
Auto braking by City SafetyCity Safety™ is applying/has applied the brakes automatically.
Windscreen Sensors blockedThe laser sensor is temporarily not functioning due to an obstruction.
• Remove the obstruction and/or clean the windshield in front of the sensor(s).
For more information on the sensor’s limitations, see page 174.
City Safety Service requiredCity Safety™ is not functioning.
• If this message remains in the display, have the system checked by a trained and qualified Volvo service technician.