2020 VOLVO S90 TWIN ENGINE ABS

DRIVER SUPPORT
* Option/accessory.
274
Collision risk warning from driver support (p. 296)
Head-up display
* (p. 139)
Activating or deactivating Distance Alert 8
Distance Alert can be turned off. The function is only available in vehicles that can displayinformation on the windshield with a head-up display *.
Activate or deactivate the function using this button inthe center display's Functionview.
GREEN button indicator light – the func- tion is activated.
GRAY button indicator light – the functionis deactivated.
Distance Alert is automatically activated eachtime the engine is started.
Related information
Distance Alert
* (p. 273)
Distance Alert limitations (p. 274)
Distance Alert limitations 9
Distance Alert functionality may be reduced in certain situations. The function is onlyavailable in vehicles that can display informa-tion on the windshield with a head-up dis- play *.
WARNING
Detection ability may be affected by vehicle size, e.g. motorcycles, whichcan cause the warning light to come onat a shorter time interval than that setor cause the warning to be temporarilyabsent.
Very high speeds can cause the light tocome on at a shorter time interval thanthat set due to limitations in the rangeof the radar unit.
NOTE
The function uses the vehicle's camera and radar sensor, which has certain generallimitations.
Related information

Distance Alert
* (p. 273)
Camera/radar sensor limitations (p. 309)
Head-up display
* (p. 139)
8
Distance Alert
9 Distance Alert

STARTING AND DRIVING
}}
403
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 anumber of automatic brake assist functions.These systems provide assistance by e.g. thedriver not needing to depress the brake pedalat a traffic light or when starting up a hill. Depending on how the vehicle is equipped, the following brake assist functions may beincluded:
Auto-hold brake function at a standstill(Auto Hold)
Hill Start Assist (Hill Start Assist)
Braking assist after a collision
City Safety
Related information
Brakes (p. 403)
Parking brake (p. 406)
Auto-hold brakes (p. 410)
Braking assist after a collision (p. 412)
Hill Start Assist (p. 411)
City Safety
™ (p. 314)
Brakes
The brake pedal is used to apply the vehicle's regular brakes, which are part of the brakesystem.
The vehicle is equipped with two brake cir- cuits. If one brake circuit is damaged, thebrake pedal will go down further whendepressed. More pressure will then berequired from the driver for normal brakingeffect.
WARNING
The power brakes only work when the electric motor or combustion engine is run-ning.
If the brake pedal is used when the engine is switched off, greater pressure must be appliedto brake 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.
Anti-lock brakesThe vehicle is equipped with an Anti-lock Braking System (ABS 2
), which helps prevent
the wheels from locking and helps maintain steering control when braking. Vibrations maybe felt from the brake pedal when ABS isoperating, which is normal. After the vehicle is started, a brief test of theABS system is automatically performed whenthe driver releases the brake pedal. An addi-tional automatic test of the system may beperformed when the vehicle is traveling at alow speed. During the test, the brake pedalmay feel as though it is pulsating.
Light braking charges the hybrid
battery
When the brakes are applied lightly, the elec-tric motor braking function is used. This con-verts the vehicle's kinetic energy into electricalenergy, which is used to charge the hybridbattery. When the battery is being chargedwith the electric motor braking function, thiswill be indicated in the instrument panel.
2 Anti-lock Braking System

||
STARTING AND DRIVING
404
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 usedto augment braking. This is indicated in theinstrument panel with the pointer down in thered area.
Symbols in the instrument panel
Symbol Meaning
A
BCheck the brake fluid level. If the level is low, fill brake fluid andcheck to determine the reasonfor the loss of brake fluid.
A
BFault in pedal sensor.
Symbol Meaning
A
B
Steady glow for 2 seconds after the engine is started: Automaticfunction check. Steady glow for more than 2 seconds: Fault in the ABS sys-tem. The vehicle's regular brakesystem is still working, but with-out the ABS function.
If the message Brake pedal
Characteristics changed Serv- ice required
is displayed, the
"Brake-by-wire" system is not functioning properly. Greaterpressure will be required to brakethe vehicle.
A In Canada.
B In the US.

STARTING AND DRIVING
405
WARNING
If the warning symbols for both brake fault and ABS fault are lit simultaneously, theremay be a fault in the brake system.
If the brake fluid reservoir level is nor- mal when this occurs, drive carefully tothe nearest workshop to have thebrake system checked - an authorizedVolvo workshop is recommended.
If the brake fluid has fallen below theMIN
level in the brake fluid reservoir,
the vehicle should not be driven untilthe brake fluid has been filled. The rea-son for the brake fluid loss must bechecked.
Related information
Brake Assist System (p. 405)
Auto-hold brakes (p. 410)
Hill Start Assist (p. 411)
Braking on wet roads (p. 405)
Braking on salted roads (p. 406)
Maintenance of the brake system(p. 406)
Brake lights (p. 158)
Brake Assist System The brake enhancing system, (BAS 3
), helps
increase braking force and can thereby reduce braking distance.
The system monitors the driver's braking hab- its and increases braking force when neces-sary. Braking force can be increased up to thepoint at which the ABS intervenes. The func-tion is deactivated when pressure on the brakepedal is decreased.
Related information
Brakes (p. 403)
Braking on wet roads
Prolonged driving in heavy rain without brak- ing may cause braking effect to be slightlydelayed the first time the brakes are applied.
This may also occur after washing the vehicle. It will then be necessary to apply greater pres-sure to the brake pedal. You should thereforemaintain a greater distance to the vehicleahead. Firmly apply the brakes after washing the vehicle or driving on wet roads. This helpswarm up the brake discs, enabling them to drymore quickly and protecting them against cor-rosion. Consider the current traffic situationwhen braking.
Related information
Brakes (p. 403)
Braking on salted roads (p. 406)
3
Brake Assist System

STARTING AND DRIVING
}}
419
Starting and stopping the combustion engine in Twin Enginevehicles An advanced control system determines the distance that the vehicle can be driven on thecombustion engine, electric motor, or both atthe same time. When driving on only theelectric motor, the vehicle may automaticallystart the combustion engine due to outsidecircumstances, e.g. low ambient tempera-tures. This is completely normal. The com-bustion engine will also always start whenthe hybrid battery is nearly fully discharged.
Climate settings at low temperaturesAt low ambient temperatures, the combustion engine will sometimes start automatically tohelp achieve the desired passenger compart-ment temperature and air quality. The amountof time the combustion engine is running canbe affected 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 maybe reduced and affect how often the combus-tion engine automatically starts.
Emission control systemTo help ensure that the emission control sys-tem is as energy-efficient as possible, thecombustion engine will run for several minutesafter it is started. The amount of time the com-bustion engine needs to be used variesdepending on the temperature of the three-way catalytic converter.
WARNING
California Proposition 65 Operating, servicing and maintaining a pas- senger vehicle can expose you to chemi-cals including engine exhaust, carbon mon-oxide, phthalates, and lead, which areknown to the State of California to causecancer and birth defects or other reproduc-tive harm. To minimize exposure, avoidbreathing exhaust, do not idle the engineexcept as necessary, service your vehicle ina well ventilated area and wear gloves orwash your hands frequently when servicingyour vehicle. For more information go towww.P65Warnings.ca.gov/passenger-vehicle.
Related information
Drive systems (p. 418)
Economical driving (p. 428)
Drive modes (p. 419)
Drive modes
Drive modes affect the vehicle's driving cha- racteristics in different ways to enhance andsimplify the driving experience in certaintypes of situations.
Drive modes enable easy access to the vehi- cle's many functions and settings in differentdriving situations. Each drive mode is adaptedto help optimize driving characteristics. Steering
Engine/transmission/all-wheel drive
Brakes
Shock absorbers
Instrument panel
Climate control settings
Select the drive mode that is adapted to the current driving conditions. Keep in mind thatnot all drive modes are available in all situa-tions.
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 todetect for children, pedestrians, cyclists oranimals. This is particularly true at lowspeeds, e.g. in parking lots.

STARTING AND DRIVING
}}
* Option/accessory.425
Leveling control * and suspension
Self-leveling and suspension functions are controlled automatically.
Rear leveling control keeps the rear section of the vehicle at the same height regardless ofload. Leveling control may also remain activewhen the vehicle is parked.
Shock absorbers (Four-C)On vehicles equipped with Four-C, the shockabsorbers are adapted to the selected drive mode and the current vehicle speed. Theshock absorbers are normally set to help opti-mize comfort and are adjusted continuouslyaccording to the road surface and the vehicle'sacceleration, braking and cornering.
TransportingWhen transporting the vehicle on a ferry, trainor truck, only secure (lash) the vehicle aroundthe tires, not using any other parts of the chas-sis. Changes in the pneumatic suspension
may occur during transport, which couldadversely affect the lashing and result in dam-age.
Symbols and messages in driver display
Symbol Message Meaning
Suspension Deactivated by userActive chassis has been switched off manually by the user.
Suspension Temporarily reduced performanceActive chassis performance has been temporarily reduced due to extensive system use. If this message appears frequently (e.g. several times in one week) contact a workshop
A
.

||
STARTING AND DRIVING
430
Factors the driver cannot control
There are several outside conditions that affect range to varying degrees: the current traffic situation
driving short distances
topography
ambient temperature and headwinds
road conditions and road surface.
The table shows the approximate relationshipbetween ambient temperature and drivingrange with normal climate settings and withclimate settings turned off. Up to a certain limit, warmer ambient temper- atures increase the electric motor's drivingrange.
Ambient temperature Climatesettingsturned offNormalclimatesettings
30 °C (86 °F) 95 % 80 %
20 °C (68 °F) 100 % 90%
10 °C (50 °F) 90 % 80 %
0 °C (32 °F) 80 % 60 %
-10 °C (14 °F) 70 % 40 %
Factors the driver can control
The driver should be aware that the following factors help conserve energy and improvedriving range: charging the battery regularly
preconditioning

Pure drive mode
climate control settings
speed and acceleration
the
Hold function
tires and tire pressure.
The table shows the approximate relationship between constant speed and driving range.Driving at a lower constant speed helpsincrease the electric motor's driving range.
Constant speed
100 km/h (62 mph) 50 %80 km/h (50 mph) 70 %60 km/h (37 mph) 90 %
50 km/h (31 mph) 100 %
NOTE
The values shown in the table refer to a new vehicle.
None of the values are absolute, butare instead affected by e.g. drivingstyle, environment and other condi-tions.
Related information
Economical driving (p. 428)
Hold and Charge functions (p. 431)
Drive modes (p. 419)

WHEELS AND TIRES
}}
* Option/accessory.529
Recommended tire pressure
The tire pressure placard on the driver's side B pillar (between the front and the rear door)indicates tire pressure for different loads andspeed conditions.
The decal specifies the designation for the fac- tory-mounted tires on the vehicle, as well asload limits and inflation pressures.
Related information
Checking tire pressure (p. 527)
Approved tire pressure (p. 634)
Tire pressure monitoring system
*
The tire pressure monitoring system 6
pro-
vides a warning symbol in the instrument panel if pressure is too low in one or moretires.
This symbol illuminates to indicate low inflation pressure. If there is a system malfunction, the inflation pressure warning symbol
will flash for approximately one minute andthen glow steadily.
System descriptionThe tire pressure monitoring system measures differences in rotational speed between thewheels through the ABS system to determineif the tires are properly inflated. If inflationpressure in a tire is too low, its diameter (andconsequently its rotational speed) changes. Bycomparing the tires with each other, the sys-tem can determine if the pressure in one ormore tires is too low.
General information about the tire pressure monitoring system
In the following description, the tire monitor- ing system is generally referred to as TPMS. Each tire, including the spare (if provided) 7
should be checked monthly when cold and inflated to the inflation pressure recom- mended by the vehicle manufacturer on thevehicle placard or tire inflation pressure label.(If your vehicle has tires of a different size thanthe size indicated on the vehicle placard or tireinflation pressure label, you should determinethe proper tire inflation pressure for thosetires.) As an added safety feature, your vehicle has been equipped with a tire pressure monitoringsystem (TPMS) that illuminates a low tirepressure telltale when one or more of yourtires is significantly under-inflated. Accord-ingly, when the low tire pressure telltale illumi-nates, you should stop and check your tires assoon as possible, and inflate them to theproper pressure. Driving on a significantly under-inflated tire causes the tire to overheat and can lead to tirefailure. Under-inflation also reduces fuel effi-ciency and tire tread life, and may affect thevehicle's handling and stopping ability. Pleasenote that the TPMS is not a substitute forproper tire maintenance, and it is the driver'sresponsibility to maintain correct tire pressure,even if under-inflation has not reached thelevel to trigger illumination of the TPMS lowtire pressure telltale. Your vehicle has also been equipped with a TPMS malfunction indicator to indicate when
6
Tire Pressure Monitoring System (TPMS)
7 Not available on all models.