2017 VOLVO XC90 TWIN ENGINE HYBRID Owners Manual

S T A R T I N G A N D D R I V I N G

STARTING AND DRIVING
* Option/accessory, for more information, see Introduction.376
Starting and driving
The vehicle is equipped with an automatic trans-mission that also makes it possible to shift gearsmanually.
Certain functions can also be used when theengine is not running, depending on the ignitionmode being used.

Related information
•Starting the engine (p. 402)
•Ignition modes (p. 400)
•Automatic transmission (p. 424)
•Opening/closing the fuel filler door (p. 393)
•Parking brake (p. 382)
Brakes
The brake system is a hydraulic system consist-ing of two separate brake circuits. If a problemshould occur in one of these circuits, it is stillpossible to stop the vehicle with the other brakecircuit.
Brake system
If one of the brake circuits is not functioning,more pressure will be needed on the brake pedal(and the pedal will go down farther) for normalbraking effect.
If the brake pedal must be depressed fartherthan normal and requires greater foot pressure,the stopping distance will be longer.
Pressure on the brake pedal is enhanced by thepower braking function.

WARNING
If the vehicle does not have electrical currentand both the electric motor and gasolineengine are switched off, the brakes cannot beused to stop the vehicle.
When the Hill Start Assist function is being used,it will take slightly longer for the brake pedal toreturn to its normal position if the vehicle isparked on an incline or uneven surface.
When driving in very hilly areas or if the vehicle iscarrying a heavy load, using brake mode B toaugment the brakes or the Off Road* drive
mode can also be used on steep downgrades toincrease the engine braking effect at low speeds.
Anti-lock Braking System ABS
The ABS system helps to improve vehicle control(stopping and steering) during severe brakingconditions by limiting brake lockup.
When ABS is operating, there may be somevibration in the brake pedal, which is normal.
The system performs a brief self-diagnostic testwhen the engine has been started and driverreleases the brake pedal. Another automatic testmay be performed when the vehicle first reachesa speed of approximately 6 mph (10 km/h). Thebrake pedal will pulsate several times and asound may be audible from the ABS controlmodule, which is normal.

Function check when the engine is
started
A Plug-in Hybrid is equipped with a "brake bywire" brake system. A function check is per-formed each time the engine is started and thedriver depresses the brake pedal to move thegear selector from P.
In certain cases, a message may appear in theinstrument panel saying that pressure on thebrake pedal is too low. Press harder on the pedal.

Light braking charges the hybrid battery
When the brakes are applied lightly, the electricmotor's braking function is used, which converts

STARTING AND DRIVING
}}
* Option/accessory, for more information, see Introduction.377
kinetic energy into electricity that is used tocharge the hybrid battery. This is indicated in theinstrument panel, see also the article "Generalinformation about the XC90 T8 Twin EnginePlug-in Hybrid".
Battery charging gauge in the instrument panel
This function is active at speeds from approx.90 mph (150 km/h) down to 3 mph (5 km/h).When braking at speeds outside of this range orduring harder braking, the hydraulic brake systemis used.

Cleaning the brake discs
Coatings of dirt and water on the brake discsmay result in delayed brake function. This delay isminimized by cleaning the brake linings.
Cleaning the brake pads is advisable in wetweather, prior to long-term parking, and after thevehicle has been washed. Do this by braking gen-tly for a short period while the vehicle is moving.
Driving on wet or salted roads
Prolonged driving on wet or salted roads canaffect brake function and increase stopping dis-tance. Be sure to keep a safe distance to thevehicle ahead when driving under these condi-tions.

Brake pad inspection
On vehicles equipped with a jack*, the conditionof the brake pads can be checked by raising thevehicle and performing a visual inspection of thebrake pads.

WARNING
•If the vehicle has been driven immediatelyprior to a brake pad inspection, the wheelhub, brake components, etc., will be veryhot. Allow time for these components tocool before carrying out the inspection.
•Apply the parking brake and put the gearselector in the Park (P) position.
•Block the wheels standing on the ground,use rigid wooden blocks or large stones.
WARNING
•Use the jack intended for the vehiclewhen changing a tire. For any other job,use stands to support the vehicle.
•The jack should be kept well-greased andclean, and should not be damaged.
•Be sure the jack is on a firm, level, non-slippery surface.
•No objects should be placed between thebase of jack and the ground, or betweenthe jack and the attachment bar on thevehicle.
•The jack must correctly engage the jackattachment.
•Never allow any part of your body to beextended under a vehicle supported by ajack.

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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)

STARTING AND DRIVING
379
Auto-hold brake function
With the Auto-hold brake function, the driver canrelease the brake pedal and the brakes willremain applied, for example, when the vehiclehas stopped at a traffic light or intersection.
When the vehicle is no longer moving forward,Auto-hold applies the brakes automatically, eitherusing the normal brakes or the parking brake.The brakes will be released when the acceleratorpedal is depressed.
If the driver's door is opened or the engine isturned off, the parking brake will be applied auto-matically.

Auto-hold control
Auto-hold control and indicator light
Turn Auto-hold on or off by pressing the controlin the tunnel console. The indicator light illumi-nates when the function is on.
When Auto-hold is off, Hill Start Assist (HSA) willbe activated to help prevent the vehicle from roll-ing backwards when starting up a hill.
Instrument panel symbol
SymbolExplanation
The symbol in the instrumentpanel illuminates when this func-tion is using the normal brakes tokeep the vehicle stationary.
A
B
This symbol in the instrumentpanel illuminates when Auto-holdis using the parking brake to keepthe vehicle stationary
AUS modelsBCanadian models

Related information
•Hill Start Assist (p. 381)
•Brake functions (p. 378)
Brake assist system
The Brake Assist System (BAS) increases brak-ing force, thereby helping reduce braking dis-tance.
The system monitors the driver's braking habitsand increases braking force when necessary.Brake force can be increased up to the point atwhich the ABS system is activated. The functionis deactivated when pressure on the brake pedaldecreases.
Related information
•Brakes (p. 376)

STARTING AND DRIVING
380
Braking effect after a collision
In certain types of collisions, the vehicle's brakesare applied to help prevent or mitigate a secon-dary collision.
Maintaining control of the vehicle after a collisionmay be difficult. To help avoid or mitigate theeffect of a secondary collision, the brakes areapplied automatically to help bring the vehicle toa stop.
The brake lights and hazard warning flashers willbe activated and the flashers will remain on afterthe vehicle has come to a standstill. The parkingbrake will then be applied automatically.
In a situation where stopping the vehicle may notbe desirable, the driver can override this systemby pressing the accelerator pedal.
This feature can only function if the brake systemis intact after the collision.

Related information
•Brake functions (p. 378)
•Airbag system (p. 71)
•Rear Collision Warning (RCW) (p. 338)
Emergency brake lights
The emergency brake lights activate in the eventof hard braking/rapid deceleration at most nor-mal driving speeds or if the ABS system is acti-vated. This function causes an additional taillighton each side of the vehicle to illuminate to helpalert vehicles traveling behind.
Once the emergency brake lights have been acti-vated, if the driver releases the brake pedal, thebrake lights will return to their normal function.
Related information
•Brakes (p. 376)
•Hazard warning flashers (p. 151)
•Brake lights (p. 151)
Hill Descent Control (HDC)
HDC is a type of low-speed automatic enginebrake and makes it possible to increase ordecrease the vehicle's speed on steep downhillgradients using only the accelerator pedal, with-out applying the brakes.
HDC is integrated into the Off Road drivemode.
HDC is particularly useful when driving downsteep hills with rough surfaces, and where theroad may have slippery patches.

WARNING
HDC does not function in all situations, and isa supplementary braking aid. The driver hasfull responsibility for driving in a safe manner.

Function
HDC allows the vehicle to roll forward or inreverse at very low speed with enhanced enginebraking. However, speed can be adjusted withthe accelerator pedal. When the acceleratorpedal is released, the vehicle will return to verylow speed.
The driver can use the brakes to slow or stop thevehicle at any time.
HDC is activated along with Low Speed Control(LSC), which together make driving on slipperysurfaces at low speeds easier.

STARTING AND DRIVING
* Option/accessory, for more information, see Introduction.381
When HDC and LSC are activated, this changesthe response from the accelerator pedal andengine.

Activating HDC
This function can be activated in different ways,depending on how the vehicle is equipped.

Using the drive mode control *
Select the Off Road drive mode to activate thefunction.
Select a different drive mode to turn HDC off. Ifthis is done while the vehicle is on a steep down-grade, engine braking will decrease gradually.
From the center display's Function view
Models without the drive modecontrol have a button for HillDescent Control in the centerdisplay's Function view.
•Tap the button to activate. A light in the but-ton illuminates when the function is acti-vated.

NOTE
The function is deactivated when driving athigher speeds and must be reactivated atlower speeds if so desired.

Related information
•Brake functions (p. 378)
•Low Speed Control (LSC) (p. 428)
•Drive modes (p. 420)
Hill Start Assist
Hill Start Assist (HSA) helps prevent the vehiclefrom rolling backwards when starting up a hill. Ifyou are backing up a hill, HSA helps prevent thevehicle from rolling forward.
HSA makes it easier to start or back up on a hillby retaining pressure on the brake pedal for sev-eral seconds after the pedal has been released inorder to keep the vehicle at a standstill.
The brakes will be released after several secondsor when the driver presses the accelerator pedal.
HSA is available even if the Auto-hold brakingfunction is turned off.
Related information
•Brake functions (p. 378)
•Auto-hold brake function (p. 379)

STARTING AND DRIVING
382
Parking brake
The electric parking brake helps to keep thevehicle stationary when it is parked.
Parking brake control in the tunnel console between thefront seats

NOTE
•A faint sound from the parking brake'selectric motor can be heard when theparking brake is being applied. Thissound can also be heard during the auto-matic function check of the parkingbrake.
•The brake pedal will move slightly whenthe electric parking brake is applied orreleased.
If the vehicle is not moving when the parkingbrake is applied, only the rear wheels are affec-
ted. If it is applied while the vehicle is moving, thenormal brakes are used on all four wheels. Thebrakes will only be applied on the rear wheelsonce the vehicle has stopped.
Related information
•Brake functions (p. 378)
•Using the parking brake (p. 382)
•Parking brake malfunctions (p. 384)
Using the parking brake
The electric parking brake helps to keep thevehicle stationary when it is parked.
Applying the parking brake
1.Put the gear selector in P.
2.Press firmly on the brake pedal.
3. Pull up the control.
> The symbol in the instrument panelflashes while the parking brake is beingapplied and glows steadily when the park-ing brake has been fully applied.
4. Release the brake pedal and ensure that thevehicle is stationary.