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* Option/accessory.431
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. In vehicles equipped with drive mode control *,
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 will return to very low speed regardless of how steepthe hill is and without the brakes needing to beapplied. 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, the feel of the accelerator pedal and engine responsewill 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. 432)
• Changing drive mode
* (p. 419)
• Low Speed Control
* (p. 429)
• All Wheel Drive (AWD)
* (p. 417)
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432
Activating and deactivating Hill
Descent 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.
Related information
• Hill Descent Control
* (p. 431)
• Changing drive mode
* (p. 419)
Economical driving
Drive economically and environmentally con- scious by thinking ahead, avoiding rapid startsand stops and adapting driving style and speedto the current traffic conditions.
Driving economically conserves natural resources
Observe the following rules:
• Do not warm up the engine by idling. It is better to begin driving normally immediately after starting the engine. A cold engine uses more fuel than a warm engine and is subject to increased wear.
• Whenever possible, avoid using the vehicle todrive short distances. The engine does nothave time to reach a normal operating tem-perature and this leads to increased fuelconsumption.
• Maintain a steady speed and a generous fol-lowing distance to traffic ahead to minimizebraking.
• For lower fuel consumption, activate Ecodrive mode.
• Use the Eco Coast function in drive mode Eco - engine braking is deactivated, allowing the vehicle's kinetic energy to be used to rollgreater distances.
• Use gear
D as often as possible and avoid
using the kick-down function.
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433
•
Fuel consumption is increased at high speeds - air resistance increases with speed.
• Remove unnecessary items from the vehicle- the heavier the load, the higher the fuelconsumption.
• Maintain the correct pressure in the tires andcheck pressure regularly.
• The type of tires used could affect fuel con-sumption - consult a retailer for advice onsuitable tires.
• Do not use winter tires after the winter sea-son has ended.
• Roof loads increase air resistance andincrease fuel consumption. Remove roofboxes, ski racks, etc. that are not in use.
• Avoid driving with the windows open.
• Using the trip computer's fuel consumptionindicators can help you learn how to drivemore economically.
Other factors that decrease fuel
consumption
• Dirty air cleaner.
• Dirty engine oil and clogged oil filter.
• Incorrect front-end alignment.
• Incorrect wheel alignment.
Some of the above items and others are checked as part of Volvo's standard maintenance sched-ule.
Related information
• Drive-E
‒ purer driving pleasure (p. 27)
• ECO drive mode (p. 420)
• Checking tire pressure (p. 529)
Preparing for a long trip
It is important to have the vehicle's systems and equipment checked carefully before driving longdistances.
Check that:
• the engine is running properly and that fuel consumption is normal
• there are no leaks (fuel, oil or other fluid)
• the brake pedal is functioning optimally
• all lights are working
‒
adjust the headlight
height if the vehicle is carrying a heavy load
• tire tread depth and air pressure are at cor-rect levels. Change to snow tires when driv-ing in areas where there is a risk of snowy oricy roads.
• the start battery is sufficiently charged
• the wiper blades are in good condition
Related information
• Checking tire pressure (p. 529)
• Filling washer fluid (p. 626)
• Winter driving (p. 434)
• Economical driving (p. 432)
• Vehicle modem settings (p. 505)
• Loading recommendations (p. 561)
• Driving with a trailer (p. 443)
• Pilot Assist (p. 303)
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434•
Speed limiter (p. 270)
• Tire sealing system (p. 545)
Winter driving
It is important to check the vehicle before driving in cold/snowy conditions to make sure it can bedriven safely.
Before the cold season arrives:
• Make sure the engine coolant contains 50% antifreeze. This mixture helps protect theengine from frost erosion down toapprox. -35 °C (-31 °F). Do not mix differenttypes of antifreeze as this could pose ahealth risk.
• Keep the fuel tank well filled to prevent con-densation from forming.
• Check the viscosity of the engine oil. Oil withlow viscosity (thinner oil) improves cold-weather starting and reduces fuel consump-tion when driving with a cold engine.
CAUTION
Low-viscosity oil should not be used with hard driving or in hot weather.
•
Check the condition and charge level of the start battery. Cold weather places greaterdemands on the start battery and reduces itscapacity.
• Use washer fluid containing antifreeze tohelp prevent ice from forming in the washerfluid reservoir.
Slippery driving conditionsFor optimal traction and roadholding, Volvo rec-ommends using snow tires on all wheels when-ever there is a risk of snow or ice on the road.
NOTE
Certain countries require use of winter tires by law. Not all countries permit the use ofstudded tires.
Practice driving on slippery surfaces under con- trolled conditions to learn how the vehicle reacts.
Related information
•Snow tires (p. 543)
• Snow chains (p. 544)
• Braking on salted roads (p. 405)
• Braking on wet roads (p. 404)
• Filling washer fluid (p. 626)
• Start battery (p. 592)
• Replacing windshield wiper blades (p. 624)
• Changing rear window wipers (p. 623)
• Refilling coolant (p. 586)
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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.
The vehicle can be driven through water up to a depth of 40 cm (15.7 in) at no more than walkingspeed. Be particularly careful when drivingthrough flowing water. When driving through standing water, drive slowly and do not stop the vehicle. When you havepassed the water, press lightly on the brake pedaland check that the brakes are functioning prop-erly. Water, mud, slush, etc. can make the brakelinings slippery, resulting in delayed brakingeffect.
• If the vehicle is equipped with contacts for anelectric heater or trailer coupling, clean theseafter driving in water or mud.
• Do not allow the vehicle to stand in water upto the sills any longer than absolutely neces-sary. This could result in electrical malfunc-tions.
CAUTION
•Engine damage could occur if water enters the air cleaner.
• If water enters the transmission, the lubri-cating ability of the oils is reduced andthe service life of these systems is short-ened.
• Damage to any component, engine,transmission, turbocharger, differential orits internal components caused by flood-ing, vapor lock or insufficient oil is notcovered under warranty.
• If the engine stalls while the vehicle is inwater, do not attempt to restart it. Havethe vehicle towed out of the water to aworkshop. An authorized Volvo workshopis recommended. Risk of engine failure.
Related information
• Recovery (p. 450)
• Low Speed Control
* (p. 429)
Opening/closing the fuel filler door The vehicle must be unlocked before the fuel filler door can be opened 6
.
An arrow next to the fuel pump symbol in the instrument panelindicates the side of the vehicleon which the fuel filler door islocated.
1. Open the fuel filler door by pressing lightly
on its rear edge.
2. After refueling, press the fuel filler door lightly to close it.
Related information
• Refueling (p. 436)
6
Only locking and unlocking using the remote key, Passive Entry or Volvo On Call will affect the status of the fuel filler door.
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RefuelingThe fuel tank is equipped with a fuel filling sys- tem without a cover.
Refueling the vehicle at a service station
Refueling is done as follows.
1. Turn off the engine and open the fuel filler door.
2. Select a fuel approved for use in the vehicle. For more information on approved fuels, see the section on "Gasoline".
3. Insert the pump's nozzle into the fuel filler pipe's opening. There are two flaps justinside the fuel filler pipe and the pump's noz-zle must push both of these flaps openbefore fuel can be added. 4. Avoid overfilling the tank. Do not press the
handle on the filler nozzle again after it hasinitially stopped pumping.
> The fuel tank is now filled.
NOTE
An over-full tank may overflow in hot weather.
CAUTION
Avoid spilling gasoline during refueling. In addition to causing damage to the environ-ment, gasolines containing alcohol can causedamage to painted surfaces, which may notbe covered under the New Vehicle LimitedWarranty.
Refueling from a fuel containerWhen filling from a fuel container, use the funnel provided in a foam block under the floor hatch inthe cargo compartment.
1. Open the fuel filler door.
2. Insert the funnel into the fuel filler pipe'sopening. There are two flaps just inside the fuel filler pipe and the tube section of thefunnel must push both of these flaps openbefore fuel can be added.
Related information
• Opening/closing the fuel filler door (p. 435)
Fuel Volvo recommends the use of detergent gaso- line to control engine deposits.
Deposit control gasoline (gasoline with detergent additives)
Detergent gasoline is effective in keeping injec- tors and intake valves clean. Consistent use ofdeposit control gasolines will help ensure gooddriveability and fuel economy. If you are not surewhether the gasoline contains deposit controladditives, check with the service station operator.
NOTE
Volvo recommends not using external fuel injector cleaning systems, e.g. do not adddetergent additives to gasoline before or afterrefueling.
Unleaded fuelAll Volvo vehicles have a three-way catalytic con- verter and must only use unleaded gasoline. USand Canadian regulations require that pumpsdelivering unleaded gasoline are labeled"UNLEADED". Only the nozzles of these pumpswill fit in your vehicle's fuel filler inlet. It is unlaw-ful to dispense leaded fuel into a vehicle labeled"unleaded gasoline only". Leaded gasoline dam-ages the three-way catalytic converter and theheated oxygen sensor system. Repeated use ofleaded gasoline will lessen the effectiveness of
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the emission control system and could result in loss of emission warranty coverage. State andlocal vehicle inspection programs will makedetection of misfueling easier, possibly resultingin emission test failure for misfueled vehicles.
NOTE
Some U.S. and Canadian gasolines contain an octane enhancing additive called methyl-cyclopentadienyl manganese tricarbonyl(MMT). If such fuels are used, your EmissionControl System performance may be affected,and the Check Engine Light (malfunctionindicator light) located on your instrumentpanel may light. If this occurs, please returnyour vehicle to a trained and qualified Volvoservice technician for service.
Gasoline containing alcohol and ethers, "Oxygenated fuels"
Some fuel suppliers sell gasoline containing "oxygenates" which are usually alcohols orethers. In some areas, state or local laws requirethat the service pump be marked indicating useof alcohols or ethers. However, there are areas inwhich the pumps are unmarked. If you are notsure whether there is alcohol or ethers in thegasoline you buy, check with the service stationoperator. To meet seasonal air quality standards,some areas require the use of "oxygenated" fuel.
Volvo permits the use of the following "oxygen-ated" fuels. However, the specified octane ratingsmust still be met.
Alcohol - Ethanol
Fuels containing up to 10% ethanol by volume may be used. Ethanol may also be referred to asEthyl alcohol, or "Gasohol". Ethers - MTBE/ETBE: Fuels containing up to 15% MTBE/ETBE may be used.
MethanolDo not use gasolines containing methanol(methyl alcohol, wood alcohol). This practice canresult in vehicle performance deterioration andcan damage critical parts in the fuel system. Suchdamage may not be covered under the NewVehicle Limited Warranty.
Related information
•
Octane rating (p. 437)
• Opening/closing the fuel filler door (p. 435)
• Refueling (p. 436)
• Emission controls (p. 439)
Octane rating Volvo demands premium fuel (91 octane 7
or
higher) for all T5, T6 and T8 engines. See both supplied decal examples.
7 AKI (Anti Knock Index) is an average value of RON (Research Octane Number) and MON (Motor Octane Number) - (RON)+(MON)/2
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Minimum octane
Decals
Sample fuel pump octane label7
.
Decal on the inside of the fuel filler flap on cars that require premium fuel 8
.
TOP TIER Detergent GasolineVolvo endorses the use of "TOP TIER Detergent Gasoline" where available to help maintainengine performance and reliability. TOP TIERDetergent Gasoline meets a new standard jointlyestablished by leading automotive manufacturesto meet the needs of today's advanced engines.Qualifying gasoline retailers (stations) will, inmost cases, identify their gasoline as having metthe "TOP TIER Detergent Gasoline" standards.
NOTE
Information about TOP TIER Detergent Gaso- line is available at www.toptiergas.com.
NOTE
When switching to higher octane fuel or changing gasoline brands, it may be neces-sary to fill the tank more than once before adifference in engine operation is noticeable.
Fuel FormulationsDo not use gasoline that contains lead or manga- nese as a knock inhibitor, and do not use leadadditives. Besides damaging the exhaust emis-sion control systems on your vehicle, lead hasbeen strongly linked to certain forms of cancer. Many fuels contain benzene as a solvent.Unburned benzene has been strongly linked tocertain forms of cancer. If you live in an areawhere you must fill your own gas tank, take pre-cautions. These may include: •
standing upwind away from the filler nozzle while refueling
• refueling only at gas stations with vaporrecovery systems that fully seal the mouth ofthe filler neck during refueling
• wearing neoprene gloves while handling afuel filler nozzle.
Use of AdditivesWith the exception of gas line antifreeze duringwinter months, do not add solvents, thickeners, orother store-bought additives to your vehicle'sfuel, cooling, or lubricating systems. Overuse maydamage your engine, and some of these additivescontain organically volatile chemicals. Do notneedlessly expose yourself to these chemicals.
WARNING
Never carry a cell phone that is
switched on
while refueling your vehicle. If the phone rings, this may cause a spark that could ignite gaso-line fumes, resulting in fire and injury.
7 AKI (Anti Knock Index) is an average value of RON (Research Octane Number) and MON (Motor Octane Number) - (RON)+(MON)/2
8 For supplementary information - see the car's Service and Warranty Booklet.