2019 VOLVO S90 TWIN ENGINE warning

WHEELS AND TIRES
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Tires
The function of the tires is to carry loads, providetraction on road surfaces, reduce vibrations andprotect the wheels from wear.
The tires significantly influence the vehicle's driv-ing characteristics. The type, dimensions, tirepressure and speed rating have a considerableimpact on how the vehicle performs.
Your vehicle is equipped with tires according tothe vehicle's tire information placard on the B-pil-lar (the structural member at the side of the vehi-cle, at the rear of the driver's door opening).

WARNING
A damaged tire could cause the driver to losecontrol of the vehicle.
CAUTION
Some Volvo models are equipped with anUltra High Performance tire and wheel com-bination designed to provide maximum drypavement performance with consideration forhydroplaning resistance. They may be moresusceptible to road hazard damage and,depending on driving conditions, may achievea tread life of less than 30,000 km (20,000miles). Even if this vehicle is equipped withVolvo's advanced AWD or stability system,these tires are not designed for winter driving,and should be replaced with winter tires whenweather conditions dictate.
The tires have good road holding characteristicsand offer good handling on dry and wet surfaces.It should be noted however that the tires havebeen developed to give these features on snow/ice-free surfaces.
Most models are equipped with "all-season" tires,which provide a somewhat higher degree of road-holding on slippery road surfaces than tires with-out the "all-season" rating. However, for optimalroadholding on icy or snow-covered roads, Volvorecommends snow tires on all four wheels.
When replacing tires, be sure that the new tiresare the same size designation, type (radial) andpreferably from the same manufacturer, on all
four wheels. Otherwise there is a risk of alteringthe vehicle's roadholding and handling characte-ristics.

Recommended tires
On delivery, the car is equipped with Volvo origi-
nal tires that have the VOL1 marking on the sideof the tires. These tires have been designed spe-cifically for your vehicle. It is therefore importantwhen replacing tires that the new tires have thissame marking to help maintain the vehicle's driv-ing characteristics, comfort and fuel consumption.

New tires
Tires are perishable goods. After a few years,they will begin to harden and their friction proper-ties will gradually deteriorate. Always replace tireswith the freshest tires possible. This is particularlyimportant for snow tires. A series of numbers is
1This may vary for certain tire dimensions.

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WARNING
The wheel and tire sizes for your Volvoare specified to meet stringent stabilityand handling requirements. Unapprovedwheel/tire size combinations can nega-tively affect your vehicle's stability andhandling.
Any damage caused by installation ofunapproved wheel/tire size combinationswill not be covered by your new vehiclewarranty. Volvo assumes no responsibilityfor death, injury, or expenses that mayresult from such installations.

Related information
Checking tire pressure (p. 549)
Tire direction of rotation (p. 544)
Tread wear indicator (p. 545)
Tire pressure monitoring system* (p. 551)
Tire sealing system (p. 564)
Uniform Tire Quality Grading (p. 548)
Tire terminology (p. 545)
Tire sidewall designations (p. 546)
Loading recommendations (p. 580)
Tire direction of rotation
Tires with tread designed to roll in only onedirection are marked with an arrow on the side-wall.
The arrow shows the tire's direction of rotation.
The tire should maintain the same directionof rotation throughout its service life.
Tires should only be moved between thefront and back, never from right to left or viceversa.
Incorrectly mounted tires impair the vehicle'sbraking properties and ability to force asiderain, snow and slush.
The tires with the most tread should alwaysbe mounted on the rear wheels to helpreduce the risk of skidding.
NOTE
Use tires of the same type, dimensions andmake (manufacturer) on each axle.

Related information
Tires (p. 542)

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545
Tread wear indicator
The tread wear indicator shows the status of thetire's tread.
The tread wear indicator is a narrow elevatedstrip running across the tire's longitudinal treadgrooves. The letters TWI (Tread Wear Indicator)are visible on the side of the tire. When approxi-mately 1.6 mm (1/16 inch) is left on the tread,the tread will be at the same height as the treadwear indicator. Replace the tire as soon as possi-ble. Tires with low tread offer very poor traction inrain or snow.

Related information
Tires (p. 542)
Tire terminology
The following is a glossary of tire-related terms.
The tire suppliers may have additional markings,notes or warnings such as standard load, radialtubeless, etc.
Tire information placard: A placard show-ing the OE (Original Equipment) tire sizes,recommended inflation pressure, and themaximum weight the vehicle can carry.
Tire Identification Number (TIN): A numberon the sidewall of each tire providing infor-mation about the tire brand and manufactur-ing plant, tire size and date of manufacture.
Inflation pressure: A measure of theamount of air in a tire.
Standard load: A class of P-metric or Metrictires designed to carry a maximum load at 35psi [37 psi (2.5 bar) for Metric tires]. Increas-ing the inflation pressure beyond this pres-sure will not increase the tires load carryingcapability.
Extra load: A class of P-metric or Metrictires designed to carry a heavier maximumload at 41 psi [43 psi (2.9 bar) for Metrictires]. Increasing the inflation pressurebeyond this pressure will not increase thetire's load carrying capability.
kPa: Kilopascal, a metric unit of air pressure.
PSI: Pounds per square inch, a standard unitof air pressure.
B-pillar: The structural member at the sideof the vehicle behind the front door.
Bead area of the tire: Area of the tire nextto the rim.
Sidewall of the tire: Area between the beadarea and the tread.
Tread area of the tire: Area of the perime-ter of the tire that contacts the road whenmounted on the vehicle.
Rim: The metal support (wheel) for a tire or atire and tube assembly upon which the tirebeads are seated.
Maximum load rating: a figure indicatingthe maximum load in pounds and kilogramsthat can be carried by the tire. This rating isestablished by the tire manufacturer.
Maximum permissible inflation pressure:the greatest amount of air pressure thatshould ever be put in the tire. This limit is setby the tire manufacturer.
Recommended tire inflation pressure:inflation pressure, established by Volvo,which is based on the type of tires that aremounted on a vehicle at the factory. Thisinformation can be found on the tire inflationplacard(s) located on the driver's side B-pillarand in the tire inflation table in this chapter.
Cold tires: The tires are considered to becold when they have the same temperatureas the surrounding (ambient) air. This tem-

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NOTE
The tire's load index and speed rating maynot appear on the sidewall because they arenot required by law.
7.M+S or M/S = Mud and Snow, AT = All Ter-rain, AS = All Season
8.U.S. DOT Tire Identification Number(TIN): This begins with the letters "DOT" andindicates that the tire meets all federalstandards. The next two numbers are thefactory code where the tire was manufac-tured, the next two are the tire size code andthe last four numbers represent the weekand year the tire was made. For example,0717 means that the tire was manufacturedduring week 7 of 2017. The numbers inbetween are marketing codes used at themanufacturer's discretion. This informationhelps a tire manufacturer identify a tire forsafety recall purposes.
9.Tire Ply Composition and Material Used:Indicates the number of plies indicates or thenumber of layers of rubber-coated fabric inthe tire tread and sidewall. Tire manufactur-ers also must indicate the ply materials in thetire and the sidewall, which include steel,nylon, polyester, and others.
10.Maximum Load: Indicates the maximumload in pounds and kilograms that can becarried by the tire. Refer to the vehicle's tire
information placard located on the B-Pillarfor the correct tire pressure for your vehicle.
11.Treadwear, Traction, and Temperaturegrades.
12.Maximum permissible inflation pressure:the greatest amount of air pressure thatshould ever be put in the tire. This limit is setby the tire manufacturer.

Speed Symbol
A tire's Speed Symbol (SS) indicates the maxi-mum speed for which the tire has been certifiedand should be at least equivalent to the vehicle'stop speed.
Winter tires, with or without studs, are exceptionsand may use a lower SS. When winter tires areinstalled, the vehicle may not be driven fasterthan the tires' SS.
The vehicle's speed should always be determinedby the posted speed limit and traffic and roadconditions, not the tire's SS.
The following table indicates the maximum per-missible speed for each SS.
M 130 km/h (81 mph)
Q 160 km/h (100 mph)
T190 km/h (118 mph)
H 210 km/h (130 mph)
V 240 km/h (149 mph)
W 270 km/h (168 mph)
Y300 km/h (186 mph)
WARNING
The wheel and tire sizes for your Volvoare specified to meet stringent stabilityand handling requirements. Unapprovedwheel/tire size combinations can nega-tively affect your vehicle's stability andhandling.
Any damage caused by installation ofunapproved wheel/tire size combinationswill not be covered by your new vehiclewarranty. Volvo assumes no responsibilityfor death, injury, or expenses that mayresult from such installations.

Related information
Tires (p. 542)

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Uniform Tire Quality Grading
ALL PASSENGER VEHICLE TIRES MUSTCONFORM TO FEDERAL SAFETY REQUIRE-MENTS IN ADDITION TO THESE GRADES.
Quality grades can be found, where applica-ble, on the tire sidewall between the treadshoulder and maximum section width. Forexample:
Treadwear 200 Traction AA Temperature A

TREADWEAR
The treadwear grade is a comparative ratingbased on the wear rate of the tire when testedunder controlled conditions on a specified gov-ernment test course. For example, a tire graded150 would wear one and one half (1 ½) times aswell on the government course as a tire graded100. The relative performance of tires dependsupon the actual conditions of their use, however,and many depart significantly from the norm dueto variation in driving habits, maintenance practi-ces and differences in road characteristics andclimate.

TRACTION
The traction grades, from highest to lowest, areAA, A, B, and C, as measured under controlledconditions on specified government test surfacesof asphalt and concrete. A tire marked C mayhave poor traction performance.
WARNING
The traction grade assigned to this tire isbased on braking (straight-ahead) tractiontests and is not a measure of cornering (turn-ing) traction.

TEMPERATURE
The temperature grades are A (the highest), B,and C, representing the tire's resistance to thegeneration of heat and its ability to dissipate heatwhen tested under controlled conditions on aspecified indoor laboratory test wheel. Sustainedhigh temperature can cause the material of thetire to degenerate and reduce tire life, and exces-sive temperature can lead to sudden tire failure.The grade C corresponds to a minimum level ofperformance that all passenger vehicle tires mustmeet under the Federal Motor Safety StandardNo. 109. Grades B and A represent higher levelsof performance on the laboratory test wheel thanthe minimum required by law.

WARNING
The temperature grade for this tire is estab-lished for a tire that is properly inflated andnot overloaded. Excessive speed, under-infla-tion, or excessive loading, either separately orin combination, can cause heat buildup andtire failure.
Related information
Tires (p. 542)
Tire sidewall designations (p. 546)

WHEELS AND TIRES
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Checking tire pressure
Correct inflation pressure helps improve drivingstability, save fuel and increase the service life ofthe tires.
Tire pressure decreases over time, which is nor-mal. Tire pressure also varies depending on theambient temperature. Driving on under-inflatedtires could cause the vehicle to overheat and leadto damage. Tire pressure affects traveling com-fort, road noise and driving characteristics.
Check the pressure in the tires every month. Usethe recommended inflation pressure for cold tiresfor optimal tire performance and wear. Under-inflated or over-inflated tires could cause uneventread wear.
Use an air pressure gauge and check the infla-tion pressure on all the tires, including the spare
tire4, at least once a month and before long trips.Volvo strongly recommends buying a reliable airpressure gauge, as the automatic gauges provi-ded at service stations may be inaccurate.

WARNING
Under-inflation is the most commoncause of tire failure and may result insevere tire cracking, tread separation, or"blow-out," with unexpected loss of vehi-cle control and increased risk of injury.
Under-inflated tires reduce the load car-rying capacity of your vehicle.

Cold tires
Inflation pressure should be checked when thetires are cold.
The tires are considered to be cold when theyhave the same temperature as the surrounding(ambient) air.
This temperature is normally reached after thevehicle has been parked for at least 3 hours.
After driving for approximately 1.6 km (1 mile),the tires are considered to be warm. If you needto drive longer than that to inflate the tires, checkand record the inflation pressure of the tires firstand inflate accordingly when you arrive at thepump.
When the ambient temperature changes, so doesthe inflation pressure. A 10-degree temperaturedrop causes a corresponding drop in inflationpressure of 1 psi (7 kPa). Check the inflationpressure of the tires regularly and adjust to the
correct pressure, which can be found on the vehi-cle's tire information placard or certification label.
If you check inflation pressure when the tires arewarm, you should never release air. The tiresbecome warm after driving and it is normal forwarm tires to have an inflation pressure abovethe recommended pressure for cold tires. A warmtire with an inflation pressure equal to or underthe recommended pressure for cold tires couldbe significantly under-inflated.

Related information
Adjusting tire pressure (p. 550)
Recommended tire pressure (p. 551)
Tire pressure monitoring system* (p. 551)
Tires (p. 542)
4Not available in all models.

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Recommended tire pressure
The tire pressure placard on the driver's side Bpillar (between the front and the rear door) indi-cates tire pressure for different loads and speedconditions.
The decal specifies the designation for the fac-tory-mounted tires on the vehicle, as well as loadlimits and inflation pressures.

Related information
Checking tire pressure (p. 549)
Approved tire pressure (p. 649)
Tire pressure monitoring system*
The tire pressure monitoring system6 provides awarning symbol in the instrument panel if pres-sure is too low in one or more tires.
Symbol Explanation
This symbol illuminates to indicatelow inflation pressure.
If there is a system malfunction, theinflation pressure warning symbolwill flash for approximately oneminute and then glow steadily.
System description
The tire pressure monitoring system measuresdifferences in rotational speed between thewheels through the ABS system to determine ifthe tires are properly inflated. If inflation pressurein a tire is too low, its diameter (and consequentlyits rotational speed) changes. By comparing thetires with each other, the system can determine ifthe pressure in one or more tires is too low.

General information about the tire pressure
monitoring system
In the following description, the tire monitoringsystem is generally referred to as TPMS.
Each tire, including the spare (if provided)7
should be checked monthly when cold and infla-
ted to the inflation pressure recommended by thevehicle manufacturer on the vehicle placard ortire inflation pressure label. (If your vehicle hastires of a different size than the size indicated onthe vehicle placard or tire inflation pressure label,you should determine the proper tire inflationpressure for those tires.)
As an added safety feature, your vehicle hasbeen equipped with a tire pressure monitoringsystem (TPMS) that illuminates a low tire pres-sure telltale when one or more of your tires issignificantly under-inflated. Accordingly, when thelow tire pressure telltale illuminates, you shouldstop and check your tires as soon as possible,and inflate them to the proper pressure.
Driving on a significantly under-inflated tire cau-ses the tire to overheat and can lead to tire fail-ure. Under-inflation also reduces fuel efficiencyand tire tread life, and may affect the vehicle'shandling and stopping ability. Please note thatthe TPMS is not a substitute for proper tire main-tenance, and it is the driver's responsibility tomaintain correct tire pressure, even if under-infla-tion has not reached the level to trigger illumina-tion of the TPMS low tire pressure telltale.
Your vehicle has also been equipped with aTPMS malfunction indicator to indicate when thesystem is not operating properly. The TPMS mal-function indicator is combined with the low tire
6Tire Pressure Monitoring System (TPMS)7Not available on all models.

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pressure telltale. When the system detects a mal-function, the telltale will flash for approximatelyone minute and then remain continuously illumi-nated. This sequence will continue upon subse-quent vehicle start-ups as long as the malfunc-tion exists. When the malfunction indicator is illu-minated, the system may not be able to detect orsignal low tire pressure as intended.
TPMS malfunctions may occur for a variety ofreasons, including the installation of replacementor alternate tires or wheels on the vehicle thatprevent the TPMS from functioning properly.
Always check the TPMS malfunction telltale afterreplacing one or more tires or wheels on yourvehicle to ensure that the replacement or alter-nate tires and wheels allow the TPMS to con-tinue to function properly.

Messages in the instrument panel
If tire pressure is too low, the low tire pressurewarning symbol is shown in the instrument panelalong with a message.
Tire pressure low Check tires, calibrateafter fill
Tire pressure system Temporarilyunavailable
Tire pressure system Service required
To keep in mind
Always calibrate the system after changingwheels or adjusting tire pressure. See the tirepressure placard on the driver's side B pillarfor Volvo-recommended tire pressures.
If you switch to a tire of another size than thefactory-mounted tires, the system must becalibrated for these tires to avoid false warn-ings.
If a spare wheel8 is used, it is possible thatthe tire pressure monitoring system will notwork correctly due to the differencesbetween the wheels.
The system does not replace the need forregular tire inspection and maintenance.
It is not possible to deactivate the tire pres-sure monitoring system.

WARNING
Incorrect inflation pressure could lead totire failure, which could cause the driverto lose control of the vehicle.
The system cannot predict sudden tiredamage.
Related information
Recommended tire pressure (p. 551)
Viewing tire pressure status in the centerdisplay* (p. 554)
Action when warned of low tire pressure(p. 555)
Calibrating the tire pressure monitoring sys-tem* (p. 553)
8Not available on all models.