brake VOLVO XC90 TWIN ENGINE 2020 Repair Manual

HYBRID INFORMATION
394
General information about Twin Engine Twin Engine vehicles are driven just like any other vehicle, but certain functions differ froma vehicle powered exclusively by gasoline.The electric motor powers the vehicle primar-ily at low speeds; the gasoline engine is usedat higher speeds or during more active driv-ing.
The instrument panel displays Twin Engine- specific information - charging information,selected drive mode, distance to dischargedbattery and hybrid battery charge level. Different drive modes can be selected while driving, e.g. electric power only or, if morepower is needed, a combination of electric andgasoline power. The vehicle calculates a com-bination of driveability, driving experience,environmental impact and fuel economy forthe selected drive mode. In order to function optimally, the hybrid bat- tery (and its electrical drive systems) and thegasoline engine (and its drive systems) mustbe at the correct operating temperature. Bat-tery capacity can be considerably reduced ifthe battery is too cold or too hot. Precondi-tioning prepares the vehicle's drive systemsand passenger compartment before driving tohelp reduce both wear and energy consump-tion. It also helps increase the hybrid battery'srange.The hybrid battery which powers the electricmotor is recharged using the charging cable. Itcan also be recharged during light braking andthrough engine braking in gear position
B. The
combustion engine can also help recharge thehybrid battery.
Important
No electrical current
Keep in mind that if there is no electrical cur- rent to the vehicle, i.e. the ignition is switchedoff or the start battery is discharged, certainfunctions such as brakes, power steering, etc.will not work.
WARNING
If the vehicle does not have electrical cur- rent and both the electric motor and thegasoline engine are switched off, thebrakes cannot be used to stop the vehicle.
Towing not permitted
Never tow a Twin Engine vehicle behind another vehicle, as this could damage theelectric motor.
Exterior engine noise
Because there is no sound from the engine when only the electric motor is running, thevehicle is equipped with artificial exteriorbackground noise. This sound is intended tohelp warn children, pedestrians, cyclists, ani- mals, etc. outside the vehicle of the vehicle'sapproach.
High-voltage electrical current
WARNING
A number of electrical components in Twin Engine Plug-in Hybrid vehicles use high-voltage current and can be extremely dan-gerous if handled incorrectly. These com-ponents and any orange wiring in the vehi-cle may only be handled by trained andqualified Volvo service technicians.
Do not touch anything that is not clearly described in this Owner's Manual.
Related information
Charging the hybrid battery (p. 395)
Hybrid gauge (p. 89)
Drive modes (p. 433)
Starting and stopping preconditioning(p. 234)
Hybrid battery (p. 617)

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HYBRID INFORMATION
396
Charging cable handle and charging socket.
Charging status is indicated in three ways:
The indicator lights in the charging module (the unit connected to the wall outlet).
Indicator light in the vehicle's chargingsocket.
Images and text in the instrument panel.
The start battery is charged while the hybridbattery is charging and stops charging whenthe hybrid battery is fully charged. If the hybrid battery's temperature is below -10 ºC (14 ºF) or above 40 ºC (104 ºF), some
of the vehicle's functions may be reduced ornot available at all. The electric motor cannot be used if the bat- tery's temperature is too low or too high. If thePURE drive mode is selected, the gasolineengine will start.
Charging using the gasoline engine
The vehicle generates electrical current to charge the battery, e.g. when the driver lightly presses the brakepedal or when engine braking is used on down-grades.
The vehicle can also generate current to the hybrid battery to charge it. The hybrid battery can also be recharged by lightly depressing the brake pedal, i.e.during light braking. This converts thevehicle's kinetic energy to electricalenergy, which is used to charge the hybridbattery.
In gear position
B, the electric motor
brakes the vehicle when the acceleratorpedal is released and the hybrid battery isrecharged at the same time.
The combustion engine can also helprecharge the hybrid battery.
Related information
Charge cable (p. 397)
Charging current (p. 397)
Opening and closing the charging socketcover (p. 400)
Initiating hybrid battery charging (p. 401)
Stopping hybrid battery charging (p. 407)
Charging status in the charging cable'scharging module (p. 403)
Charging status in the vehicle's chargingsocket (p. 403)
Charging status in the instrument panel(p. 405)
Twin Engine symbols and messages in theinstrument panel (p. 408)
Automatic transmission (p. 427)
Changing drive mode (p. 438)
Long-term storage of vehicles with hybridbatteries (p. 410)

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HYBRID INFORMATION
406
NOTE
If the instrument panel is not used, it will go dark after a period of time. To reactivatethe display: depress the brake pedal,
open one of the doors, or
put the ignition in mode
I by turning
the START knob clockwise and then
releasing.
Related information
Charging the hybrid battery (p. 395)
Twin Engine symbols and messages in the instrument panel (p. 408)
Charging status in the vehicle's chargingsocket (p. 403)
Charging status in the charging cable'scharging module (p. 403)
Stopping hybrid battery charging (p. 407)

STARTING AND DRIVING
* Option/accessory.
412
Starting the vehicle
The vehicle can be started using the start knob in the tunnel console when the remotekey is in the passenger compartment.
Start knob in the tunnel console.
WARNING
Before starting:
Buckle your seat belt.
Adjust the seat, steering wheel and mirrors.
Make sure you can fully depress thebrake pedal.
The remote key is not physically used to startthe ignition because the vehicle is equippedwith the keyless Passive Start system. To start the vehicle:
CAUTION
The vehicle cannot be started if the charg- ing cable is still plugged in. Make sure topull out the charging cable from the charg-ing socket before starting the vehicle.
1. The remote key must be inside the vehicle.
For vehicles with Passive Start, the key must be in the front section of the passen-ger compartment. With the optional key- less locking/unlocking function *, the key
can be anywhere in the vehicle.
2. Press and hold down the brake pedal 1
as
far as possible.
3. Turn the start knob clockwise and release. The control will automatically return to the original position.
WARNING
Never use more than one inlay mat at a time on the driver's floor. If any othertype of floor mat is used, remove theoriginal mat from the driver's seat floorbefore driving. All types of mats mustbe securely anchored in the attach-ment points in the floor. Make sure thefloor mat does not impede the move-ment of the brake pedal or acceleratorpedal in any way, as this could be aserious safety hazard.
Volvo's floor mats are specially manu-factured for your vehicle. They must beproperly secured in the attachmentpoints in the floor to help ensure theycannot slide and become trappedunder the pedals.
The starter motor will crank until the enginestarts or until overheating protection is trig-gered. During normal start conditions, the vehicle's electric motor will be prioritized and the gaso-line engine will remain off. This means thatonce the start knob is turned clockwise, theelectric motor has been "started" and the vehi-cle is ready to be driven. The warning andinformation symbols in the instrument panel
1 If the vehicle is moving, it is only necessary to turn the start knob clockwise to start the engine.

STARTING AND DRIVING
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413
will go out and the selected theme will be dis- played to indicate that the electric motor isactivated. In some situations, such as in cold weather or if the hybrid battery's charge level is too low,the gasoline engine will start instead.
Error messagesIf the Vehicle key not found message is
shown in the instrument panel at start, place the remote key at the backup reader and thenmake a new start attempt.
Location of the backup reader in the tunnel console.
NOTE
When the remote key is placed in the backup reader, make sure that no othervehicle keys, metal objects or electronicdevices (e.g. cellular phones, tablets, lap-tops or chargers) are in the backup reader.Multiple vehicle keys close to each other inthe backup reader can disrupt their func-tionality.
If Vehicle start System check, wait is dis-
played in the instrument panel while attempt- ing to start the vehicle, wait until the messagedisappears and try again to start the vehicle.
CAUTION
If the engine has not responded after 3 attempts – wait for 3 minutes before star-ting a new attempt. Starting capabilityincreases if the starter battery is given timeto recover.
NOTE
The vehicle cannot be started if the hybrid battery is discharged.
WARNING
Never remove the remote control key from
the vehicle while driving.
WARNING
Always remove the remote key from the passenger compartment when youleave the vehicle and make sure theignition is in mode
0.
Always put the gear selector in
P and
apply the parking brake before leavingthe vehicle. Never leave the vehicleunsupervised while the engine is run-ning.
Always open the garage door fully andmake sure that ventilation is very goodbefore starting the engine in a garage.The exhaust fumes produced by thevehicle contain carbon monoxide,which is invisible and odorless but verytoxic.

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STARTING AND DRIVING
* Option/accessory.
416
Mode Functions
I The panoramic roof, power windows, 12-volt electricalsocket in the passenger com-partment, Bluetooth, naviga-tion, phone, blower and wind-shield wipers can be used.
The power seats can beadjusted.
The 12-volt electrical socket
* in
the cargo compartment can beused.
Electrical current will be taken
from the battery in this ignitionmode.
II The headlights illuminate.
Warning/indicator lights illumi-nate for 5 seconds.
A number of other systems areactivated. However, seat andrear window heating can onlybe activated when the engineis running.
This ignition mode uses a lot of
current from the battery andshould be avoided wheneverpossible!
A Also activated when the door is opened.
Related information
Starting the vehicle (p. 412)
Adjusting the steering wheel (p. 206)
Jump starting using another battery (p. 459)
Selecting ignition mode (p. 416)
Selecting ignition mode
The vehicle's ignition can be put in various modes (levels) to make different functionsavailable.
Selecting an ignition mode
Start knob in the tunnel console.
Ignition mode 0
– Unlock the vehicle and
keep the remote key in the passenger compartment.
NOTE
To set level I or II without engine start –
do not depress the brake pedal (or clutch
pedal for vehicles with manual transmis- sion) when selecting this ignition mode.
Ignition mode I
– Turn the start knob
clockwise and release it. The control will

STARTING AND DRIVING
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417
automatically return to the original posi- tion.
Ignition mode II
– Turn the start knob
clockwise and hold it there forapprox. 5 seconds. Release the knob,which will automatically return to its origi-nal position.
Back to ignition mode 0
– To return to
ignition mode 0 from modes I and II, turn
the start knob clockwise and release it.The control will automatically return to theoriginal position.
Related information
Starting the vehicle (p. 412)
Switching off the vehicle (p. 414)
Ignition modes (p. 415)
Adjusting the steering wheel (p. 206)
Jump starting using another battery(p. 459)
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, when starting up a hill orwhen driving down 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
Hill Descent Control (Hill Descent Control)
Related information
Brakes (p. 417)
Parking brake (p. 421)
Auto-hold brakes (p. 424)
Braking assist after a collision (p. 426)
Hill Start Assist (p. 426)
City Safety
™ (p. 327)
Hill Descent Control (p. 445)
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. Use the Off Road drive mode to increase the engine braking effect when driving on steepdowngrades at low speeds.
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 may

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STARTING AND DRIVING
418be felt from the brake pedal when ABS is operating, which is normal. After the vehicle is started, a brief test of the ABS 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.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
B Check 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.
2
Anti-lock Braking System

STARTING AND DRIVING
419
Symbol Meaning
A
BSteady 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.
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. 419)
Auto-hold brakes (p. 424)
Hill Start Assist (p. 426)
Braking on wet roads (p. 420)
Braking on salted roads (p. 420)
Maintenance of the brake system (p. 420)
Brake lights (p. 164)
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. 417)
3
Brake Assist System

STARTING AND DRIVING
420
Braking on wet roadsProlonged 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. 417)
Braking on salted roads (p. 420)
Braking on salted roads
When driving on salted roads, a layer of salt may form on the brake discs and brake pads.
This could increase stopping distance. Main- tain an extra large safety distance to the vehi-cle ahead. Make sure to also:
Apply the brakes from time to time to helpremove salt. Make sure braking does notpose a risk to any other road users.
Gently apply the brakes when you havefinished driving and before driving again.
Related information
Brakes (p. 417)
Braking on wet roads (p. 420)
Maintenance of the brake system
Regularly check the brake system compo- nents for wear.
To keep the vehicle as safe and reliable as possible, follow the Volvo service schedulespecified in the Warranty and MaintenanceRecords Information booklet. After replacingbrake pads and brake discs, braking effect isnot adapted until they are "broken in" by driv-ing a few hundred kilometers (miles). Com-pensate for the reduced braking effect byapplying greater pressure to the brake pedal.Volvo recommends only using brake padsapproved for your Volvo.
CAUTION
The brake system's components should be regularly checked for wear. Contact a workshop for advice on how to do this or let a workshop perform theinspection - an authorized Volvo workshopis recommended.
Related information
Brakes (p. 417)