2017 VOLVO XC90 TWIN ENGINE HYBRID stop start

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
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* 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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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)

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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.

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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.

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385
Before a long distance trip
It is always worthwhile to have your vehiclechecked by a trained and qualified Volvo servicetechnician before driving long distances. Yourretailer will also be able to supply you with bulbs,fuses, spark plugs and wiper blades for your usein the event that problems occur.
As a minimum, the following items should bechecked before any long trip:
•Check that engine runs smoothly and thatfuel consumption and the oil level are normal.
•Before leaving on a trip, fill the fuel tank andmake sure the hybrid battery is fully charged.During the trip, make a habit of refueling reg-ularly.
•Check for fuel, oil, and fluid leakage.
•Check condition of drive belts.
•Check state of the battery's charge.
•Examine tires carefully and replace thosethat are worn. Also, check tire inflation pres-sure.
•The brakes, front wheel alignment, and steer-ing gear should be checked by a trained andqualified Volvo service technician only.
•Check all lights, including high beams.
•Reflective warning triangles are legallyrequired in some states/provinces.
•Have a word with a trained and qualifiedVolvo service technician if you intend to drive
in countries where it may be difficult toobtain the correct fuel.
•Consider your destination. If you will be driv-ing through an area where snow or ice arelikely to occur, consider using snow tires.
Driving economically
Better driving economy can be obtained bythinking ahead, avoiding rapid starts and stopsand adjusting the speed of your vehicle to imme-diate traffic conditions.

Driving economically with the XC90 T8
Twin Engine Plug-in Hybrid
Plan your driving in order to utilize the electricmotor as much as possible.
An energy-conserving driving style lowers currentconsumption from the hybrid battery and helpsincrease electric driving range.

Charging
•Charge the hybrid battery regularly using thecharging cable. Whenever possible, begin adrive with a fully charged battery.
•Check the location of charging points.
•Where possible, choose parking spaces withcharging points.

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Driving through standing water
The vehicle should be driven with extreme cau-tion if it is necessary to drive through standingwater.
The vehicle can be driven through water up to adepth approximately level with the floor at walk-ing speed to help prevent water from enteringthe differential and/or the transmission or dam-aging electrical components.
•If possible, check the depth of the waterbefore driving through it. Take particular carewhen driving through flowing water.
•Before driving through water, always selectthe Off Road drive mode to ensure that thegasoline engine is running and to maximizeground clearance.
•After driving through water, apply the brakesand check that they are functioning correctly.
•Clean the electrical connections for trailerwiring after driving in mud or water.
•When driving through water, maintain lowspeed and do not stop in the water.

CAUTION
•Damage may occur to the engine, trans-mission, electrical components, etc. if thevehicle is driven through water higherthan its floor level. Be aware that wavescreated by other vehicles could cause thelevel to temporarily be above the vehicle'sfloor level.
•Damage to any components due to waterabove the floor level, vapor lock or insuffi-cient oil is not covered under warranty.
•If the engine has been stopped while thevehicle is in water, do not attempt torestart it. Have the vehicle towed out ofthe water and inspected by a trained andqualified Volvo service technician.

WARNING
•Avoid driving through standing or rushingwater. Doing so can be dangerous and itmay also be difficult to determine theactual depth of the water.
•If water cannot be avoided, after drivingthrough the water, press lightly on thebrake pedal to ensure that the brakes arefunctioning normally. Water or mud canmake the brake linings slippery, resultingin delayed braking effect.

Related information
•Towing recommendations (p. 389)
Overheating the engine andtransmission
In demanding driving conditions, such as whentransporting heavy loads, driving in mountainousareas or in very hot weather there is a risk ofoverheating the engine or transmission.
•The engine's output may be slightly limited ifthere is a risk of overheating.
•Remove e.g., auxiliary lights mounted in frontof the grille in hot weather.
•If the temperature of the engine coolantbecomes too high, the warning symbol willilluminate and the message Enginetemperature/Stop safely will be displayed.Stop the vehicle as soon as possible in asafe place and let the engine idle for severalminutes.
•If the message Engine temperature/Hightemperature Turn off engine or Enginecoolant/Stop safely is displayed, stopsafely and turn off the engine.
•If the transmission begins to overheat, analternative gear shifting program will beselected. An integrated protective functionwill also by activated, the warning symbol willilluminate and the message TransmissionwarmHigh temperature Reduce speedor Transmission warmStop safely, waitfor cooling will be displayed in the instru-ment panel.

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•The air conditioning may be switched offtemporarily.
•After a prolonged period of driving, do notturn off the engine immediately after stop-ping.
•The engine cooling fan commonly continuesto run for several minutes after the enginehas been turned off.

WARNING
The cooling fan (located at the front of theengine compartment, behind the radiator) maystart or continue to operate (for up to6 minutes) after the engine has beenswitched off.

Related information
•Driving with a trailer (p. 397)
•Before a long distance trip (p. 385)
Winter driving
Check your vehicle before the approach of coldweather.
The following advice is worth noting:
•Make sure that the engine coolant contains50 percent antifreeze. Any other mixture willreduce freeze protection. This gives protec-tion against freezing down to –31 °F(–35 °C). The use of "recycled" antifreeze isnot approved by Volvo. Different types ofantifreeze must not be mixed.
•Volvo recommends using only genuine Volvoantifreeze in your vehicle's radiator.
•Try to keep the fuel tank well filled – thishelps prevent the formation of condensationin the tank. In addition, in extremely coldweather conditions it is worthwhile to addfuel line de-icer before refueling.
•The viscosity of the engine oil is important.Oil with low viscosity (thinner oil) improvescold-weather starting as well as decreasingfuel consumption while the engine is warm-ing up. Full synthetic 0W-30 oil is recom-mended for driving in areas with sustainedlow temperatures.
•The load placed on the battery is greater dur-ing the winter since the windshield wipers,lighting, etc., are used more often. Moreover,the capacity of the battery decreases as thetemperature drops. In very cold weather, apoorly charged battery can freeze and be
damaged. It is therefore advisable to checkthe state of charge more frequently andspray an anti-rust oil on the battery posts.
•Volvo recommends the use of snow tires onall four wheels for winter driving.
•To prevent the washer fluid reservoir fromfreezing, add washer solvents containingantifreeze. This is important since dirt is oftensplashed on the windshield during winterdriving, requiring the frequent use of thewashers and wipers. Volvo Washer Solventshould be diluted as follows: Down to 14 °F(–10 °C): 1 part washer solvent and 4 partswater Down to 5 °F (–15 °C): 1 part washersolvent and 3 parts water Down to 0 °F(–18 °C): 1 part washer solvent and 2 partswater Down to –18 °F (–28 °C): 1 partwasher solvent and 1 part water.
•Use Volvo Teflon Lock Spray in the locks.
•Avoid using de-icing sprays as they cancause damage to the locks.

Related information
•Snow tires and chains (p. 485)