2018 VOLVO XC90 T8 brakes

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* Option/accessory.445
Drive modes
Drive modes affect the vehicle's driving charac- teristics in different ways to enhance and sim-plify the driving experience in certain types of sit-uations.
Drive modes enable easy access to the vehicle's many functions and settings in different drivingsituations. The following systems are adapted tohelp optimize driving characteristics in each drivemode: • Steering
• Engine/transmission/all-wheel drive
• Brakes
• Pneumatic suspension
* and shock absorbers
• Instrument panel
• Climate control settings
Select the drive mode that is best suited to the current driving conditions. Keep in mind that notall drive modes are available in all situations.
Available drive modes
WARNING
Keep in mind that the vehicle does not emit any engine noise when using the electricmotor and may therefore be difficult to detectfor children, pedestrians, cyclists or animals.This is particularly true at low speeds, e.g. inparking lots.
WARNING
Do not leave the vehicle in an unventilated area with a drive mode activated and the com-bustion engine switched off. The engine willstart automatically if the charge level in thehybrid battery is low and the resulting exhaustgases can be very harmful to people and ani-mals.
HYBRID
• This is the default mode in which the electric motor and combustion engine work together.
The vehicle starts in Hybrid mode. The control system uses both the electric motor and the gas-oline engine - separately or in tandem - and cal-culates optimal utilization with regard to perform-ance, fuel consumption and comfort. At highspeeds, ground clearance is automatically low- ered 4
to reduce air resistance. Driving capacity on
the electric motor alone is determined by factors such as the hybrid battery's charge level, the need for heat/cooling in the passenger compart-ment, etc. If there is sufficient charge in the battery, it is possible to drive solely on electric power. Whenthe accelerator pedal is pressed, only the electricmotor will be activated until the battery reaches acertain charge level. Above this level, the currentin the battery cannot supply the power requestedby the accelerator pedal and the combustionengine will start. When the hybrid battery's charge level is low, the combustion engine will start more frequently tosave the remaining current in the battery. Chargethe hybrid battery from a 120-240 volt outlet using a charging cable, or activate
Charge in
Function view to reset the option of only using the electric motor. This drive mode is designed for low energy con- sumption with an optimized mix between theelectric motor and gasoline engine, without com-promising on climate comfort or driving experi-ence. When faster acceleration is requested bythe driver, the electric driveline will be utilized tohelp provide maximum additional power. Thevehicle also monitors the driving conditions andautomatically engages all-wheel drive if neces-sary. All-wheel drive and extra electric power arealways available regardless of the battery'scharging status.
4 For vehicles with pneumatic suspension.

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NOTE
When LSC with HDC is activated in the OFF ROAD drive mode, the feel of the acceleratorpedal and engine response will change.
NOTE
This drive mode is not designed to be used for normal street driving.
NOTE
The function is deactivated when driving at high speeds and must be reactivated at lowerspeeds if so desired.
Related information
•Activating and deactivating Low Speed Con- trol using the function button (p. 454)
• Changing drive mode (p. 449)
• Hill Descent Control (p. 454)
• All Wheel Drive (AWD) (p. 443)
Activating and deactivating LowSpeed Control using the functionbutton
Vehicles that are not equipped with drive mode controls in the tunnel console have a function button for Low Speed Control with
Hill Descent
Control in the center display's Function view.
Selecting Low Speed Control in the center display's Function view
–Tap the Hill Descent Control button to
activate or deactivate the function.
> An indicator light in the button will illumi- nate when the function is activated.
When the engine is switched off, the function will be automatically deactivated.
NOTE
The function is deactivated when driving at high speeds and must be reactivated at lowerspeeds if so desired.
Related information
• Low Speed Control (p. 453)
• Changing drive mode (p. 449)
Hill Descent Control The function for assisting when driving downhill, Hill Descent Control (HDC), is a low-speedfunction with increased engine braking. Thefunction makes it possible to increase ordecrease the vehicle's speed on steep downhillgradients by only using the accelerator pedal,without applying the brakes. The function is included in the Off Road drive mode.
HDC is designed for driving on rough roads at low speeds and downhill gradients with slipperyor otherwise difficult road surfaces. The driverdoes not need to use the brake pedal but caninstead focus on steering.
WARNING
HDC is only intended to be a supplementary braking aid and it does not function in all sit-uations. The driver is always ultimately responsible for operating the vehicle in a safe manner.
FunctionHill Descent Control allows the vehicle to move forward or backward at very low speeds assistedby the brake system. The driver can increase thespeed by pressing the accelerator pedal. Whenthe accelerator pedal is released, the vehicle willreturn to very low speed regardless of how steep

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the hill is and without the brakes needing to be applied. The brake lights will illuminate when thefunction is activated. The driver can brake to stop or slow the vehicle at any time by depressing the brake pedal. HDC is activated along with Low Speed Control (LSC), which facilitates and improves traction andcontrol on rough and slippery surfaces. The sys-tem is intended to be used at low speeds, up toapproximately 40 km/h (25 mph).
To keep in mind when using HDC
•
If the function is switched off while driving ona steep downhill gradient, braking effect willbe gradually reduced.
• HDC can be used in gear positions
D and R,
and in manual gears 1 or 2.
• It is not possible to manually shift to thirdgear or higher when HDC is active.
NOTE
When LSC with HDC is activated in the OFF ROAD drive mode, the feel of the acceleratorpedal and engine response will change.
NOTE
This drive mode is not designed to be used for normal street driving.
NOTE
The function is deactivated when driving at high speeds and must be reactivated at lowerspeeds if so desired.
Related information
• Activating and deactivating Hill Descent Con- trol using the function button (p. 455)
• Changing drive mode (p. 449)
• Low Speed Control (p. 453)
• All Wheel Drive (AWD) (p. 443)
Activating and deactivating HillDescent Control using the functionbutton
Vehicles that are not equipped with drive mode controls in the tunnel console have a function button for Hill Descent Control with
Hill
Descent Control in the center display's Func-
tion view.
Selecting Hill Descent Control in the center display's Function view
HDC only works at low speeds.
–Tap the Hill Descent Control button to
activate or deactivate the function.
> An indicator light in the button will illumi- nate when the function is activated.
When the engine is switched off, the function will be automatically deactivated.
NOTE
The function is deactivated when driving at high speeds and must be reactivated at lowerspeeds if so desired.

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Driving
•Choose the Pure drive mode to help mini- mize electric power consumption.
• Maintain a steady speed and a generous fol-lowing distance to traffic ahead to minimizebraking. This drive mode has the lowestpower consumption.
• Balance energy requirements using theaccelerator pedal. Use the indicator on theinstrument panel to see available electricpower and avoid starting the combustionengine unnecessarily. The electric motor ismore effective than the combustion engine,especially at low speeds.
• When braking is necessary, brake gentlyusing the brake pedal. This will recharge thehybrid battery. A regenerative function isintegrated in the brake pedal and can beaugmented by the electric motor's brakingcapacity when the gear selector is in mode B
.
• Higher speeds increase energy consumption - air resistance increases with speed.
• Activate the
Hold function in the Function
view at high speeds when traveling farther than is possible using the hybrid battery'scapacity.
• Whenever possible, avoid using the
Chargefunction to charge the hybrid battery. Charg- ing the battery using the combustion engine increases fuel consumption and carbon diox-ide emissions.
• In a cold climate, reduce heating of the wind-shield/rear window, mirrors, seats and thesteering wheel.
• Maintain the correct pressure in the tires andcheck pressure regularly.
• The type of tires used could affect energyconsumption - consult a retailer for advice onsuitable tires.
• Remove unnecessary items from the vehicle- the heavier the load, the higher the fuelconsumption.
• Roof loads increase air resistance andincrease fuel consumption. Remove roofboxes, ski racks, etc. that are not in use.
• Avoid driving with the windows open.
• Do not keep the vehicle still on an upwardgradient by using the accelerator pedal. Usethe brakes instead.
Related information
•
Drive-E
‒
purer driving pleasure (p. 27)
• Factors affecting electric motor range(p. 458)
• Using the electric motor only (p. 457)
• Hybrid gauge (p. 87)
• Checking tire pressure (p. 557)
Using the electric motor only
When using the electric motor, Volvo Twin Engine provides a combination of good fueleconomy, low emissions and high performance.
For energy-efficient driving:
• Select the Pure drive mode to help maximize driving range using only the electric motor.
• Balance energy requirements using theaccelerator pedal. Use the indicator on theinstrument panel's hybrid gauge to see avail-able electric power and avoid starting thecombustion engine unnecessarily.
• When braking is necessary, brake gentlyusing the brake pedal. This will recharge thehybrid battery.
• Activate the
Hold function in the Function
view at high speeds when traveling farther than is possible using the hybrid battery'scapacity.
• Reduce current consumption in the passen-ger compartment by reducing e.g. fan speed,electric heating, or air conditioning use.
Also follow the general economical driving adviceregarding speed, tires and load to maximizerange.
Related information
• General information about Twin Engine(p. 406)
• Economical driving (p. 456)

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Driving through standing water
Driving the vehicle through a deep pool of stand- ing water on a water-covered roadway is calledfording. This must be done with great caution.
To prevent damage to the vehicle when driving through water (e.g. on flooded roads): • Do not drive in water higher than the floor of the vehicle. If possible, check the depth ofthe water at its deepest point before drivingthrough it. Be particularly careful when driv-ing through flowing water.
• Always select the
Off Road drive mode
before driving in water to ensure the gasoline engine is running.
• Do not drive faster than walking speed.
• Do not stop the vehicle in the water. Drivecarefully forward or back the vehicle out ofthe water.
• Remember that waves created by passingvehicles could cause the water level to riseabove the vehicle's floor level.
• Avoid driving through salt water to help avoidthe risk of corrosion.
CAUTION
Parts of the vehicle (e.g. engine, transmission, driveline, electrical components, etc.) can bedamaged if the vehicle is driven through waterhigher than its floor level. Damage to anycomponents caused by flooding, vapor lock orinsufficient oil is not covered under warranty. If the engine stalls while the vehicle is in water, do not attempt to restart it. Have thevehicle towed on the bed of a tow truck to aworkshop - an authorized Volvo workshop isrecommended.
When you have passed the water, press lightly on the brake pedal and check that the brakes arefunctioning properly. Water, mud, slush, etc. canmake the brake linings slippery, resulting indelayed braking effect. If the vehicle is equipped with a trailer coupling contact, clean the contact after driving in water ormud.
Related information
•
Recovery (p. 477)
• Low Speed Control (p. 453)
Opening/closing the fuel filler door A button on the instrument panel is used to unlock the fuel filler door.
An arrow next to the fuel pump symbol in the instrument panelindicates the side of the vehicleon which the fuel filler door islocated.

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Stowing the ball holder
WARNING
When not in use, the detachable ball holder should always be properly stowed in the des-ignated location under the floor of the cargocompartment.
Related information
•Driving with a trailer (p. 472)
• Towing capacity and tongue weight (p. 660)
Driving with a trailer
There are a number of things to consider when towing a trailer, such as the towbar, the trailerand how the load is distributed in the trailer.
Load-carrying capacity is determined by the vehi- cle's curb weight. The total weight of all passen-gers and any installed accessories, e.g. towbar,reduces the vehicle's load-carrying capacity bythe corresponding amount. • Towbars used on the vehicle must be approved for the applicable use.
• Distribute the load on the trailer so that theweight on the towbar complies with thespecified maximum towball weight. Thetongue weight is calculated as part of thevehicle's payload.
• Increase the tire pressure to the recom-mended pressure for a full load.
• The engine is subjected to more load thanusual when towing a trailer.
• Towing a trailer affects the vehicle's han-dling, durability and driving economy.
• Do not drive with a heavy trailer when thevehicle is very new. Wait until the mileagehas reached at least 1000 km (620 miles).
• On long and steep downgrades, the vehicle'sbrakes are subjected to much more loadthan usual. When manually shifting, down-shift and adapt speed accordingly. •
Follow applicable regulations regarding per-mitted speed and weight.
• Drive slowly when towing a trailer up a longand steep incline.
• The maximum trailer weights given only applyto altitudes up to 1000 meters (3280 feet)above sea level. At higher altitudes, enginepower (and thus the vehicle's climbing ability)is decreased due to the reduced air density,and the maximum trailer weight must there-fore be reduced. The weight of the vehicleand trailer must be decreased by 10% foreach additional 1000 m (3280 feet) or partthereof.
• Avoid driving with a trailer on inclines of morethan 12%.
• Avoid overloading and other incorrect use.
• The trailer's brakes must be balanced withthe vehicle's brakes to help ensure safestops (follow applicable local regulations).

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CAUTION
•Bumper-attached trailer hitches must not be used on Volvos, nor should safetychains be attached to the bumper.
• Trailer hitches attaching to the vehiclerear axle must not be used.
• Never connect a trailer's hydraulic brakesystem directly to the vehicle brake sys-tem, nor a trailer's lighting system directlyto the vehicle lighting system. Consultyour nearest authorized Volvo retailer forcorrect installation.
• When towing a trailer, the trailer's safetychains or wire must be correctly fastenedto the attachment points provided in thetrailer hitch on the vehicle. The safetychain or wire must never be fastened toor wound around the towing ball.
NOTE
The optional detachable trailer hitch may not be available in all markets or on all models.Consult your Volvo retailer.
NOTE
Extreme weather conditions, towing a trailer, driving at high altitudes and fuel quality arefactors that significantly increase a vehicle'sfuel consumption.
Trailer weights
WARNING
Please adhere to the recommendations provi- ded for trailer weight. If the recommendationsare not followed, the vehicle and trailer maybe difficult to control during evasive maneu-vers and braking.
NOTE
The specified maximum trailer weights are those permitted by Volvo. National vehicleregulations may set additional restrictions ontrailer weight and speed. The trailer hitchesmay be certified for higher towing weightsthan the vehicle is permitted to tow.
Self-leveling suspension
*The vehicle's self-leveling system attempts to keep the vehicle at a constant level, regardless ofload (up to the maximum permitted weight).When the vehicle is stationary, the rear end of thevehicle will be slightly lowered, which is normal.
Driving in hilly terrain or hot weatherIn certain conditions, there is a risk of overheat-ing when driving with a trailer. If overheating ofthe engine and drive system is detected, a warn-ing symbol will illuminate in the instrument panelalong with a message. The automatic transmission selects the optimalgear for the current load and engine speed.
Steep inclines
Do not lock the automatic transmission into a higher gear than what the engine can handle
‒ it
is not always preferable to drive in high gears at low rpm.
Parking on a hill
1. Depress the brake pedal.
2. Apply the parking brake.3. Put the gear selector in P.
4. Release the brake pedal.Put chocks behind the wheels when the vehicle is parked on a hill with a trailer attached.
Starting on a hill
1. Depress the brake pedal. 2. Put the gear selector in D.
3. Release the parking brake.
4. Release the brake pedal and start driving.
Related information
• Trailer Stability Assist
* (p. 474)
• Checking trailer lights (p. 475)
• Towing capacity and tongue weight (p. 660)
• Overheating of engine and transmission (p. 468)

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Trailer Stability Assist *
Trailer Stability Assist (TSA 8
) is a function
designed to help stabilize a vehicle that is tow- ing a trailer when the vehicle and trailer havebegun to sway. The function is part of the Elec- tronic Stability Control system ESC 9
.
Reasons for swayingA vehicle towing a trailer may begin to sway for various reasons. Normally this only occurs at highspeeds. However, if the trailer is overloaded orunevenly distributed, e.g. too far back, there is arisk of swaying even at low speeds. Swaying may be caused by factors such as:
• The vehicle and trailer are hit by a sudden, strong crosswind.
• The vehicle and trailer are traveling on anuneven road or over a bump.
• Sudden movements of the steering wheel.
Once swaying has begun, it can be difficult orimpossible to stop it. This makes the vehicle andtrailer difficult to control and there is a risk ofswerving into oncoming traffic or driving off theroad.
Trailer Stability Assist functionTrailer Stability Assist continuously monitors thevehicle's movements, particularly lateral move- ments. If swaying is detected, the brakes areapplied individually on the front wheels, which hasa stabilizing effect on the vehicle and trailer. Thisis often enough to enable the driver to regaincontrol of the vehicle. If the Trailer Stability Assist function's first attempt is not adequate to stop the swayingmotion, the brakes are applied on all wheels andengine power is temporarily reduced. As theswaying motion begins to decrease and the vehi-cle and trailer have once again become stable,TSA stops regulating the brakes/engine powerand the driver regains control of the vehicle.
NOTE
Trailer Stability Assist is deactivated if the driver selects the sport mode by deactivating
ESC in the center display's menu system.
Trailer Stability Assist may not intervene if the driver tries to compensate for the swaying motionby moving the steering wheel rapidly, becausethe system will then not be able to determine if itis the trailer or the driver causing the swaying.
When Trailer Stability Assist is activated, the
ESC symbol is
displayed in the instrument panel.
Related information
• Driving with a trailer (p. 472)
• Electronic Stability Control (p. 274)
8
Trailer Stability Assist
9 Electronic Stability Control