2018 VOLVO XC90 T8 charge battery

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Brake functions
The vehicle's brakes are used to reduce speed or prevent the vehicle from rolling.
In addition to the wheel brakes and parking brakes, the vehicle is also equipped with a num-ber of automatic brake assist functions. Thesesystems help the driver by e.g. keeping the vehi-cle stationary when the brake pedal is notdepressed (e.g. at a traffic light or intersection),when starting up a hill or when driving down a hill. Depending on how the vehicle is equipped, the following brake assist functions may be included:
• Auto-hold brakes (Auto Hold)
• Hill Start Assist (Hill Start Assist)
• Braking assist after a collision
• City Safety
• Hill Descent Control (Hill Descent Control)
Related information
•
Brakes (p. 429)
• Parking brake (p. 432)
• Auto-hold brakes (p. 436)
• Braking assist after a collision (p. 437)
• Hill Start Assist (p. 437)
• City Safety
™ (p. 335)
• Hill Descent Control (p. 454)
Brakes The brake pedal is used to apply the vehicle's regular brakes, which are part of the brake sys-tem.
The vehicle is equipped with two brake circuits. If one brake circuit is damaged, the brake pedal willgo down further when depressed. More pressurewill then be required from the driver for normalbraking effect.
WARNING
If the vehicle does not have electrical current and both the electric motor and the gasolineengine are switched off, the brakes cannot beused to stop the vehicle.
In very hilly areas or when driving with a heavy load, gear position B can be used to augment the
brakes with engine braking. Use the Off Road drive mode to increase the engine braking effect when driving on steepdowngrades at low speeds.
Anti-lock brakesThe vehicle is equipped with an Anti-lock BrakingSystem (ABS), which can help prevent thewheels from locking and help maintain steeringcontrol when braking. Vibrations may be felt fromthe brake pedal when ABS is operating, which isnormal. After the vehicle is started, a brief test of the ABS system is automatically performed when the driver releases the brake pedal. An additionalautomatic test of the system may be performedwhen the vehicle is traveling at a low speed. Dur-ing the test, the brake pedal may feel as though itis pulsating.
Light braking charges the hybrid batteryWhen the brakes are applied lightly, the electricmotor braking function is used. This converts thevehicle's kinetic energy into electrical energy,which is used to charge the hybrid battery. Whenthe battery is being charged with the electricmotor braking function, this will be indicated inthe instrument panel.
When the battery is being charged with the electric motor braking function, this will be indicated in theinstrument panel.
This function is active at speeds in the range of 150-5 km/h (93-3 mph). When braking atspeeds outside of this range, or during harderbraking, the hydraulic braking system is used to

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Parking brake malfunctionIf you are unable to deactivate or activate the parking brake after several attempts, contact anauthorized Volvo workshop.
A audible warning signal will sound if the parking brake is applied while the vehicle is being driven. If the vehicle must be parked before the problem is rectified, turn the wheels as when parking on an incline and put the gear selector in P.
Low battery charge levelIf the battery charge level is too low, it will not be possible to apply or release the parking brake.Connect an auxiliary battery to the vehicle if thebattery is discharged.
Replacing brake padsDue to the design of the electric parking brake,the rear brake pads must be replaced by a work-shop. An authorized Volvo workshop is recom-mended.
Symbols in the instrument panel
SymbolMeaning
A
B A flashing symbol indicates that a fault has been detected. See themessage in the instrument panel.
A
B
Fault in the brake system. See the message in the instrument panel.
Information message in the instru- ment panel.
A
Canadian models.
B US models.
Related information
• Activating and deactivating the parking brake (p. 433)
• Start battery (p. 615)
• Volvo's service program (p. 598)

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STARTING AND DRIVING
* Option/accessory.
440 Help functions The system will automatically shift to
P:
• if the ignition is switched off while
D or R is
selected.
• if the driver unbuckles the seat belt and opens the driver's door while the vehicle isrunning with the gear selector in a gear other than
P.
To park a vehicle with an unbuckled seat belt andopen door – end P mode by shifting to R or D
again.
Reverse - R
Select R when backing up. The vehicle must be
stationary when Reverse is selected.
Neutral - N
No gear is selected and the engine can be started. Apply the parking brake if the vehicle is stationary with the gear selector in N.
To move the gear selector from Neutral to another gear, the brake pedal must be depressed and the ignition in mode II.
D drive mode
D is the normal driving gear position. The trans-
mission shifts up or down automatically depend- ing on acceleration and speed. The vehicle mustbe stationary when the gear selector is moved from R to D.
Brake - B
B can be selected at any time during a drive. In B
mode, the engine braking function is activated when the accelerator pedal is released, whichhelps charge the hybrid battery. This offers addi-tional opportunities to recharge the hybrid bat-tery, since the battery is charged even when thebrake pedal is not depressed.
B mode in the instrument panel.
From B mode, it is possible to manually shift to
lower gears. The currently selected gear (1-8) will be displayed in the instrument panel.
• Pull the gear selector backward once to shiftdown one gear.
• Pull the gear selector backward again to shiftdown to lower gears.
To shift manually to a higher gear, the vehicle must be equipped with steering wheel paddles *. •
Push the gear selector forward to return to
D
mode.
For smooth shifting and engine performance, the
transmission will shift down automatically if the vehicle's speed becomes too low for the selectedgear.
Related information
• Shiftlock (p. 442)
• Using the steering wheel paddles
* to shift
(p. 441)
• The kickdown function (p. 442)
• Gear indicator
* (p. 442)

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443
All Wheel Drive (AWD)All-wheel drive, All Wheel Drive (AWD), also called four-wheel drive, means that power is dis-tributed to all four wheels, which improves trac-tion.
The electric motor that powers the rear wheels enables electronic all-wheel drive functionality. To achieve the best traction, power is automati- cally directed to the wheels that have the bestgrip. The system continuously calculates theneed for torque to the rear wheels, and canimmediately redistribute up to half of the engine'storque to the rear wheels. All-wheel drive also has a stabilizing effect at higher speeds. In normal driving conditions, mostof the engine's power is directed to the frontwheels. When the vehicle is stationary, all-wheeldrive is always activated in preparation for maxi-mum traction during acceleration. All-wheel drive reacts differently depending on which drive mode is selected.
Related information
• Drive modes (p. 445)
• Low Speed Control (p. 453)
• Transmission (p. 438)
Drive systems
Volvo Twin Engine combines a combustion engine for the front wheels and an electric motorfor the rear wheels.
Two drive systemsDepending on the selected drive mode and power available in the electric motor, the drivesystems can either be used separately or in tan-dem. The electric motor gets its energy from a hybrid battery located under the tunnel console. Thehybrid can be charged from a wall outlet or in a special charging station. The combustion engine can also charge the hybrid battery using a special high-voltage generator. Both the combustion engine and the electric motor can generate power directly to the wheels.An advanced control system coordinates both thedrive systems to help optimize driving economy.
Hybrid battery - The hybrid battery's function is to store electrical current. This energy isprovided by plugging the charging cable intoan electrical outlet, through regenerativebraking or from the high-voltage generator.This provides current to power the electricmotor and to temporarily power the electricalair conditioning to precondition the passen-ger compartment.
Combustion engine - The combustion engine starts when the charge level in the hybridbattery is too low to provide the power outputrequested by the driver.
High-voltage generator 3
- Charges the hybrid
battery. Starter for the combustion engine.
2 This illustration is generic. The layout may vary depending on vehicle model and software updates.
3 CISG (Crank Integrated Starter Generator) - Combined high-voltage generator and starter.

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444Can provide the combustion engine with extra electrical current.
Electric motor - Powers the vehicle using electricity. Can provide extra torque andpower during acceleration. Provides electricalall-wheel drive functionality. Regeneratesbraking energy into electrical current.
Related information
•
General information about Twin Engine(p. 406)
• Starting and stopping the combustion enginein Twin Engine vehicles (p. 444)
• Drive modes (p. 445)
• Transmission (p. 438)
• Factors affecting electric motor range(p. 458)
Starting and stopping thecombustion engine in Twin Enginevehicles
An advanced control system determines the dis- tance that the vehicle can be driven on the com-bustion engine, electric motor, or both at thesame time. When driving on only the electricmotor, the vehicle may automatically start thecombustion engine due to outside circumstan-ces, e.g. low ambient temperatures. This is com-pletely normal. The combustion engine will alsoalways start when the hybrid battery is nearlyfully discharged.
Climate settings at low temperaturesAt low ambient temperatures, the combustion engine will sometimes start automatically to helpachieve the desired passenger compartmenttemperature and air quality. The amount of timethe combustion engine is running can be affec-ted by:
• lowering the temperature
• reducing blower speed
• activating Pure drive mode.
Using the electric motor in hot or cold weather
At very low or high ambient temperatures, the electric motor's driving range and power may bereduced and affect how often the combustionengine automatically starts.
Emission control systemTo help ensure that the emission control systemfunctions optimally, the combustion engine willrun for several minutes after it is started. Theamount of time the combustion engine needs tobe used varies depending on the temperature ofthe three-way catalytic converter.
Related information
•
Drive systems (p. 443)
• Economical driving (p. 456)
• Using the electric motor only (p. 457)
• Drive modes (p. 445)

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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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Information in the instrument panel
When driving in Hybrid mode, a hybrid gauge will be displayed in the instrument panel. The gaugewill indicate the amount of electrical currentrequired when the driver depresses the accelera-tor pedal. The marker between the lightning andthe drop shows how much current is available.
The instrument panel gauge when both the electric motor and the combustion engine are being used.
The instrument panel also shows how much current is being restored to thebattery (regenerated) during light brak-ing.
PURE
•Uses the electric motor only, with the lowest possible energy consumption and carbon dioxide emissions. This drive mode maximizes the use of the hybrid battery. Ground clearance is lowered
4
to reduce
air resistance and certain climate system func- tions are reduced to provide the longest possibledriving distance using only electricity. Pure mode is available when the hybrid battery is sufficiently charged. Even in Pure mode, the com-bustion engine will start if the charge level in thebattery gets too low. The combustion engine willalso start
• if the vehicle's speed goes above 125 km/h(78 mph)
• if the driver requests more power than theelectric motor can provide
• if factors such as cold weather affect thesystem or components.
This drive mode is optimized for maximum drivingdistance with electric propulsion and is primarilyintended for use in city driving. Pure helps pro-vide the lowest possible consumption even whenthe hybrid battery is fully discharged. ECO climateis activated to control the climate in the passen-ger compartment, and in slippery road conditionsslightly more wheel spin may be permitted beforeall-wheel drive is automatically activated.
ECO Climate
In Pure mode, ECO climate is automatically acti- vated in the passenger compartment to helpreduce energy consumption.
NOTE
When the Pure drive mode is activated, set-
tings for certain climate system and electricity consuming functions are reduced. Some ofthese settings can be reset manually, but fullfunctionality will only be restored by leaving
Pure mode or adapting the Individual drive
mode to full climate system functionality.
If condensation forms on the windows, tap the max defroster button, which will function normally.
4 For vehicles with pneumatic suspension.

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OFF ROAD
•Maximizes the vehicle's ability to traverse dif- ficult terrain or poor roads.
In this mode, ground clearance 4
is high, steering
is light, and all-wheel drive and Hill DescentControl are activated. This drive mode is only available at low speeds, up to 40 km/h (25 mph). If this speed is excee-ded, Off road mode will be cancelled and AWDmode will be activated instead. All-wheel drive requires both the combustion and electric motor to be in continuous operation,which results in higher fuel consumption. In Off road mode, a compass will be displayed between the speedometer and the tachometer inthe instrument panel. The permissible speedrange will be shown in the speedometer. This drive mode is optimized for maximum control when driving at low speeds on very poor roads or difficult terrain. It raises the chassis 4
, reduces
driveline throttle response, and locks the vehicle in all-wheel drive. The Hill Descent Control func-tion facilitates controlled driving on steep down-grades.NOTE
This drive mode is not designed to be used for normal street driving.
NOTE
Due to the increased ground clearance, if the OFF ROAD mode was selected when theengine was switched off, the suspension willlower when the engine is restarted.
CAUTION
Do not use the OFF ROAD drive mode when towing a trailer without an electrical connec-tion. This could result in damage to the pneu-matic suspension system's bellows.
AWD
• Improves the vehicle's traction and handling by increasing all-wheel drive.
This drive mode locks the vehicle in all-wheeldrive. An optimal distribution between front andrear axle torque helps provide the best possiblecontrol, stability and traction, e.g. on slipperyroads or when towing a heavy trailer or anothervehicle. The AWD drive mode is always availableregardless of the hybrid battery's charge status. Both the combustion engine and the electricmotor are engaged to enable all-wheel drive,which results in higher fuel consumption. In the other drive modes, the vehicle automati- cally adapts the need for all-wheel drive accord-ing to the road surface, and can activate the elec-tric motor or start the combustion engine as nee-ded.
POWER
•
Power mode is designed to provide sportier driving characteristics and a faster accelera-tion response.
This drive mode maximizes the combined powerfrom the combustion engine and the electricmotor by providing power to both the front andrear wheels. Gear shifting will be faster and moredistinct and the transmission will prioritize gearswith a higher traction force. Steering response isfaster, suspension is stiffer and ground clearance is lower 4
to help reduce body roll when cornering.
Both the combustion engine and the electric motor are engaged to enable all-wheel drive,which results in higher fuel consumption. This drive mode is optimized for maximum per- formance and throttle response. It changes thethrottle response, gear shifting program andturbo boost system. Chassis settings and steer-ing and brake response are also optimized. ThePower drive mode is always available regardlessof the hybrid battery's charge status.
4 For vehicles with pneumatic suspension.