MERCEDES-BENZ CLA 2019 Workshop Manual

passenger front air bag is enabled or disa-
bled in accordance with the person in the
front-passenger seat
Rthe front-passenger seat has been moved
back as far back as possible.
Rthe person is seated correctly.
Make sure, both before and during the jour-
ney, that the status of the front-passenger
front air bag is correct.
GWARNING
If you secure a child in a rearward-facing child
restraint system on the front-passenger seat
and the PASSENGER AIR BAG OFF indicator
lamp is off, the front-passenger front air bag
can deploy in the event of an accident. The
child could be struck by the air bag. This poses
an increased risk of injury or even fatal injury.
Make sure that the front-passenger front air
bag has been deactivated. The PASSENGER
AIR BAG OFF indicator lamp must be lit.
NEVER use a rearward-facing child restraint
on a seat protected by an ACTIVE FRONT AIR-
BAG in front of it; DEATH or SERIOUS INJURY
to the child can occur.
If the PASSENGER AIR BAG OFF indicator lampstays off, do not install a rearward-facing childrestraint system on the front-passenger seat.You can find more information on OCS under"Problems with the Occupant Classification Sys-tem" (Ypage 51).
GWARNING
If you secure a child in a forward-facing child
restraint system on the front-passenger seat
and you position the front-passenger seat too
close to the dashboard, in the event of an
accident, the child could:
Rcome into contact with the vehicle's inte-
rior if the PASSENGER AIR BAG OFF indi-
cator lamp is lit, for example
Rbe struck by the air bag if the PASSENGER
AIR BAG OFF indicator lamp is off
This poses an increased risk of injury or even
fatal injury.
Always move the front-passenger seat as far
back as possible and fully retract the seat
cushion length. Always make sure that the
shoulder belt strap is correctly routed from
the vehicle belt sash guide to the shoulder
belt guide on the child restraint system. The
shoulder belt strap must be routed forwards
and downwards from the vehicle belt sash
guide. If necessary, adjust the vehicle belt
sash guide and the front-passenger seat
accordingly. Always observe the child
restraint system manufacturer's installation
instructions.
If OCS determines that:
RThe front-passenger seat is unoccupied, thePASSENGER AIR BAG OFF indicator lamplights up after the system self-test andremains lit. This indicates that the front-passenger front air bag is deactivated.
RThe front-passenger seat is occupied by achild of up to twelve months old, in a standardchild restraint system, the PASSENGER AIRBAG OFF indicator lamp lights up after thesystem self-test and remains lit. This indi-cates that the front-passenger front air bag isdeactivated.
But even in the case of a twelve-month-oldchild, in a standard child restraint system, thePASSENGER AIR BAG OFF indicator lamp cango out after the system self-test. This indi-cates that the front-passenger front air bag isactivated. The result of the classification isdependent on, among other factors, the childrestraint system and the child's stature. It isrecommended that you install the childrestraint system on a suitable rear seat.
RThe front-passenger seat is occupied by aperson of smaller stature (e.g. a teenager orsmall adult), the PASSENGER AIR BAG OFFindicator lamp lights up and remains lit afterthe system self-test depending on the resultof the classification or, alternatively, goes out.
-If the PASSENGER AIR BAG OFF indicatorlamp is off, move the front-passenger seat
Occupant safety49
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as far back as possible. Alternatively, a per-son of smaller stature can sit on a rear seat.
-If the PASSENGER AIR BAG OFF indicatorlamp is lit, a person of smaller statureshould not use the front-passenger seat.
RThe front-passenger seat is occupied by anadult or a person of adult stature, thePASSENGER AIR BAG OFF indicator lampgoes out after the system self-test. This indi-cates that the front-passenger front air bag isactivated.
If children are traveling in the vehicle, be sure toobserve the notes on "Children in the vehicle"(Ypage 54).
When the Occupant Classification System(OCS) is malfunctioning, the redurestraintsystem warning lamp on the instrument clusterand the PASSENGER AIR BAG OFF indicatorlamp light up simultaneously. The front-passenger front air bag is deactivated in thiscase and does not deploy during an accident.Have the Occupant Classification System (OCS)checked and repaired immediately at a qualifiedspecialist workshop. Mercedes-Benz recom-mends that you use an authorized Mercedes-Benz Center for this purpose.
If the front-passenger seat, the seat cover or theseat cushion are damaged, have the necessaryrepair work carried out at a qualified specialistworkshop. Mercedes-Benz recommends thatyou use an authorized Mercedes-Benz Centerfor this purpose.
For safety reasons, Mercedes-Benz recom-mends that you only use seat accessories thathave been approved by Mercedes-Benz.
If the driver's air bag deploys, this does notmean that the front-passenger front air bag willalso deploy. The Occupant Classification Sys-tem (OCS) categorizes the occupant on thefront-passenger seat. Depending on that result,the front-passenger front air bag is either ena-bled or deactivated.
Self-check
GDANGER
If the PASSENGER AIR BAG OFF and
PASSENGER AIR BAG ON indicator lamps do
not both light up during the self-test, the sys-
tem is malfunctioning. The front-passenger
front air bag might be triggered unintention-
ally or might not be triggered at all in the event
of an accident with high deceleration. This
poses an increased risk of injury or even fatal
injury.
In this case the front-passenger seat may not
be used. Do not install a child restraint system
on the front-passenger seat. Have the Occu-
pant Classification System (OCS) checked
and repaired immediately at a qualified spe-
cialist workshop.
GWARNING
If the PASSENGER AIR BAG OFF indicator
lamp remains lit after the self-test, the front-
passenger front air bag is deactivated. It will
not be deployed in the event of an accident. In
this case, the front-passenger front air bag
cannot perform its intended protective func-
tion, e.g. when a person is seated in the front-
passenger seat.
That person could, for example, come into
contact with the vehicle's interior, especially
if the person is sitting too close to the dash-
board. This poses an increased risk of injury or
even fatal injury.
When the front-passenger seat is occupied,
always ensure that:
Rthe classification of the person in the front-
passenger seat is correct and the front-
passenger front air bag is enabled or deac-
tivated in accordance with the person in the
front-passenger seat
Rthe person is seated properly with a cor-
rectly fastened seatbelt
Rthe front-passenger seat has been moved
as far back as possible
If the PASSENGER AIR BAG OFF indicator
lamp remains lit when it should not, the front-
passenger seat must not be used. Do not
install a child restraint system on the front-
passenger seat. Have the Occupant Classifi-
cation System (OCS) checked and repaired
immediately at a qualified specialist work-
shop.
50Occupant safety
Safety

GWARNING
Objects between the seat surface and the
child restraint system could affect OCS oper-
ation. This could result in the front-passenger
air bag not functioning as intended during an
accident. This poses an increased risk of
injury or even fatal injury.
Do not place any objects between the seat
surface and the child restraint system. The
entire base of the child restraint system must
always rest on the seat cushion of the front-
passenger seat. The backrest of the forward-
facing child restraint system must, as far as
possible, be resting on the backrest of the
front-passenger seat. Always comply with the
child restraint system manufacturer's instal-
lation instructions.
After the self-test, the PASSENGER AIR BAG OFFor the PASSENGER AIR BAG ON indicator lampdisplays the status of the front-passenger frontair bag (Ypage 48). If the front-passenger frontair bag is enabled, the PASSENGER AIR BAG ONindicator lamp lights up for 60 seconds and thengoes out.
If the PASSENGER AIR BAG ON indicator lamp isoff, only the PASSENGER AIR BAG OFF indicatorlamp displays the status of the front-passengerfront air bag. The PASSENGER AIR BAG OFFindicator lamp may be lit continuously or be off.
For more information about the OCS, see "Prob-lems with the Occupant Classification System"(Ypage 51).
Problems with the Occupant Classification System (OCS)
Be sure to observe the notes on "System self-test" (Ypage 50).
Occupant safety51
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ProblemPossible causes/consequences andPPSolutions
The PASSENGER AIRBAG OFF indicator lamplights up and remains lit,even though the front-passenger seat is occu-pied by an adult or a per-son of a stature corre-sponding to that of anadult.
The classification of the person on the front-passenger seat is incor-rect.
XMake sure the conditions for a correct classification of the personon the front-passenger seat are met (Ypage 48).
XIf the PASSENGER AIR BAG OFF indicator lamp remains lit, the front-passenger seat may not be used.
XHave OCS checked as soon as possible at an authorized Mercedes-Benz Center.
The PASSENGER AIRBAG OFF indicator lampdoes not light up and/ordoes not stay on.
The front-passenger seatis:
Runoccupied
Roccupied by theweight of a child up totwelve months old in achild restraint system
OCS is malfunctioning.
XMake sure there is nothing between the seat cushion and the childseat.
XMake sure that the entire base of the child restraint system rests onthe seat cushion of the front-passenger seat. The backrest of theforward-facing child restraint system must lie as flat as possibleagainst the backrest of the front-passenger seat. If necessary,adjust the position of the front-passenger seat.
XMake sure that the seat cushion length is fully retracted.
XWhen installing the child restraint system, make sure that the seatbelt is tight. Do not pull the seat belt tight using the front-passengerseat adjustment. This could result in the seat belt and the childrestraint system being pulled too tightly.
XCheck for correct installation of the child restraint system.
Make sure that the head restraint does not apply a load to the childrestraint system. If necessary, adjust the head restraint accord-ingly.
XMake sure that no objects are applying additional weight onto theseat.
XIf the PASSENGER AIR BAG OFF indicator lamp remains off and/orthe PASSENGER AIR BAG ON indicator lamp lights up, do not installa child restraint system on the front-passenger seat. It is recom-mended that you install the child restraint system on a suitable rearseat.
XHave OCS checked as soon as possible at an authorized Mercedes-Benz Center.
Deployment of Emergency Tensioning
Devices and air bags
Important safety notes
GWARNING
The air bag parts are hot after an air bag has
been deployed. There is a risk of injury.
Do not touch the air bag parts. Have a
deployed air bag replaced at a qualified spe-
cialist workshop as soon as possible.
GWARNING
A deployed air bag no longer offers any pro-
tection and cannot provide the intended pro-
tection in an accident. There is an increased
risk of injury.
Have the vehicle towed to a qualified special-
ist workshop in order to have a deployed air
bag replaced.
It is important for your safety and that of yourpassenger to have deployed air bags replaced
52Occupant safety
Safety

and to have any malfunctioning air bagsrepaired. This will help to make sure the air bagscontinue to perform their protective function forthe vehicle occupants in the event of a crash.
GWARNING
Emergency Tensioning Devices that have
deployed pyrotechnically are no longer opera-
tional and are unable to perform their inten-
ded protective function. This poses an
increased risk of injury or even fatal injury.
Have pyrotechnically triggered Emergency
Tensioning Devices replaced immediately at a
qualified specialist workshop.
If Emergency Tensioning Devices are triggeredor air bags are deployed, you will hear a bang,and some powder may also be released. Theurestraint system warning lamp lights up.
Only in rare cases will the bang affect your hear-ing. The powder that is released generally doesnot constitute a health hazard, but it may causeshort-term breathing difficulties in people withasthma or other respiratory problems. Providedit is safe to do so, you should leave the vehicleimmediately or open the window in order to pre-vent breathing difficulties.
Air bags and pyrotechnic Emergency TensioningDevices (ETDs) contain perchlorate material,which may require special handling and regardfor the environment. National guidelines mustbe observed during disposal. In California, seewww.dtsc.ca.gov/HazardousWaste/Perchlorate/index.cfm.
Method of operation
During the first stage of a collision, the restraintsystem control unit evaluates important physi-cal data relating to vehicle deceleration or accel-eration, such as:
Rduration
Rdirection
Rintensity
Based on the evaluation of this data, therestraint system control unit triggers the Emer-gency Tensioning Devices during a head-on orrear-end collision.
An Emergency Tensioning Device can only betriggered, if:
Rthe ignition is switched on
Rthe components of the restraint system areoperational. You can find further informationunder "Restraint system warning lamp"(Ypage 41)
Rthe seat belt buckle tongue has engaged inthe belt buckle of the respective front seat
The Emergency Tensioning Devices in the rearpassenger compartment are triggered inde-pendently of the lock status of the seat belts.
If the restraint system control unit detects amore severe accident, further components ofthe restraint system are activated independ-ently of each other in certain frontal collisionsituations:
RFront air bags as well as driver's and front-passenger knee bags
RWindow curtain air bag, if the system deter-mines that deployment can offer additionalprotection to that provided by the seat belt
Depending on the person in the front-passengerseat, the front-passenger front air bag is eitherdisabled or enabled. The front-passenger frontair bag can be deployed in an accident only if thePASSENGER AIR BAG OFF indicator lamp is off.Observe the information on the PASSENGER AIRBAG indicator lamps (Ypage 41).
Your vehicle has two-stage front air bags. At thefirst deployment threshold the front air bag fillswith gas. If the second deployment threshold isthen reached within a few milliseconds, the frontair bag is filled with the maximum quantity ofgas.
The activation threshold of the Emergency Ten-sioning Devices and the air bags is determinedby evaluating the rate of vehicle deceleration oracceleration which occurs at various points inthe vehicle. This process is pre-emptive innature. Deployment should take place in goodtime at the start of the collision.
The rate of vehicle deceleration or accelerationand the direction of the force are essentiallydetermined by:
Rthe distribution of forces during the collision
Rthe collision angle
Rthe deformation characteristics of the vehicle
Rthe characteristics of the object with whichthe vehicle has collided
Factors which can only be seen and measuredafter a collision has occurred do not play a deci-
Occupant safety53
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sive role in the deployment of an air bag. Nor dothey provide an indication of air bag deploy-ment.
The vehicle can be deformed considerably, with-out an air bag being deployed. This is the case ifonly parts which are relatively easily deformedare affected and the rate of deceleration is nothigh. Conversely, air bags may be deployed eventhough the vehicle suffers only minor deforma-tion. This is the case if, for example, very rigidvehicle parts such as longitudinal body mem-bers are hit, and sufficient deceleration occursas a result.
If the restraint system control unit detects a sideimpact or if the vehicle rolls over, the applicablecomponents of the restraint system aredeployed independently of each other depend-ing on the apparent type of accident.
RSide impact air bags on the side where theimpact takes place, independently of theEmergency Tensioning Device and the use ofthe seat belt on the driver's seat and outerseats in the second row
The side impact air bag on the front-passenger side deploys under the followingconditions:
-the OCS system detects that the front-passenger seat is occupied or
-the seat belt buckle tongue is engaged inthe belt buckle of the front-passenger seat
RWindow curtain air bag on the side of impact,independently of the use of the seat belt andindependently of whether the front-passenger seat is occupied
REmergency Tensioning Devices, if the systemdetermines that deployment can offer addi-tional protection in this situation
RWindow curtain air bags on the driver's andfront-passenger side in certain situationswhen the vehicle rolls over, if the systemdetermines that deployment can offer addi-tional protection to that provided by the seatbelt
iNot all air bags are deployed in an accident.The different air bag systems work independ-ently of each other.
How the air bag system works is determinedby the severity of the accident detected,especially the vehicle deceleration or accel-eration and the apparent type of accident:
RHead-on collision
RSide impact
RRollover
Automatic measures after an acci-
dent
Immediately after an accident, the followingmeasures are implemented, depending on thetype and severity of the impact:
Rthe hazard warning lamps are switched on
Rthe emergency lighting is activated
Rthe vehicle doors are unlocked
Rthe front side windows are lowered
Rthe engine is switched off and the fuel supplyis cut off
Rvehicles with Mercedes me connect: auto-matic emergency call
Children in the vehicle
Important safety notes
Accident statistics show that children securedin the rear seats are safer than children securedin the front-passenger seat. For this reason,Mercedes-Benz strongly advises that you installa child restraint system on a rear seat. Childrenare generally better protected there.
If a child younger than twelve years old andunder 5 ft (1.50 m) in height is traveling in thevehicle:
Ralways secure the child in a child restraintsystem suitable for Mercedes-Benz vehicles.The child restraint system must be appropri-ate to the age, weight and size of the child.
Rbe sure to observe the instructions and safetynotes in this section in addition to the childrestraint system manufacturer's installationinstructions.
Ralways observe the instructions and safetynotes on the "Occupant classification system(OCS)". (Ypage 47)
54Children in the vehicle
Safety

GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking positionP.
Rstart the engine.
In addition, they may operate vehicle equip-
ment and become trapped. There is a risk of
an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
GWARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
GWARNING
If the child restraint system is subjected to
direct sunlight, parts may get very hot. Chil-
dren may burn themselves on these parts,
particularly on the metal parts of the child
restraint system. There is a risk of injury.
If you leave the vehicle, taking the child with
you, always ensure that the child restraint
system is not exposed to direct sunlight. Pro-
tect it with a blanket, for example. If the child
restraint system has been exposed to direct
sunlight, let it cool down before securing the
child in it. Never leave children unattended in
the vehicle.
Always ensure that all vehicle occupants havetheir seat belts fastened correctly and are sittingproperly. Particular attention must be paid tochildren.
Observe the safety notes on the seat belt(Ypage 42) and the notes on correct use of seatbelts (Ypage 43).
A booster seat may be necessary to achieveproper seat belt positioning for children over40 lbs (18 kg) until they reach a height where a
three-point seat belt can be properly fastenedwithout a booster seat.
Special seatbelt retractor
GWARNING
If the seat belt is released while driving, the
child restraint system will no longer be
secured properly. The special seat belt retrac-
tor is disabled and the inertia real draws in a
portion of the seat belt. The seat belt cannot
be immediately refastened. There is an
increased risk of injury, possibly even fatal.
Stop the vehicle immediately, paying atten-
tion to road and traffic conditions. Reactivate
the special seat belt retractor and secure the
child restraint system properly.
All seat belts in the vehicle, except the driver'sseat belt, are equipped with a special seat beltretractor. When activated, the special seat beltretractor ensures that the seat belt cannotslacken once the child seat is secured.
Installing a child restraint system:
XMake sure you observe the child restraintsystem manufacturer's installation instruc-tions.
XPull the seat belt smoothly from the belt out-let.
XEngage seat belt tongue in belt buckle.
Activating the special seat belt retractor:
XPull the seat belt out fully and let the inertiareel retract it again.While the seat belt is retracting, you shouldhear a ratcheting sound. The special seat beltretractor is enabled.
XPush the child restraint system down so thatthe seat belt is tight and does not loosen.
Removing the child restraint system and deac-tivating the special seat belt retractor:
XMake sure you observe the child restraintsystem manufacturer's installation instruc-tions.
XPress the release button of the seat beltbuckle and guide the seat belt tongue backtowards the belt sash guide.The special seat belt retractor is deactivated.
Children in the vehicle55
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Child restraint system
The use of seat belts and child restraint systemsis required by law in:
Rall 50 states
Rthe U.S. territories
Rthe District of Columbia
Rall Canadian provinces
If you install a rearward-facing child restraintsystem on the center rear seat, the rear arm restmust be folded back as far as possible.
You can obtain further information about thecorrect child restraint system from any author-ized Mercedes-Benz Center.
GWARNING
If the child restraint system is installed incor-
rectly on a suitable seat, it cannot protect as
intended. The child cannot then be restrained
in the event of an accident, heavy braking or
sudden changes of direction. There is an
increased risk of injury, possibly even fatal.
Make sure that you observe the child restraint
system manufacturer's installation instruc-
tions and the notes on use. Please ensure,
that the base of the child restraint system is
always resting completely on the seat cush-
ion. Never place objects, e.g. cushions, under
or behind the child restraint system. Only use
child restraint systems with the original cover
designed for them. Only replace damaged
covers with genuine covers.
GWARNING
If the child restraint system is installed incor-
rectly or is not secured, it can come loose in
the event of an accident, heavy braking or a
sudden change in direction. The child
restraint system could be thrown about, strik-
ing vehicle occupants. There is an increased
risk of injury, possibly even fatal.
Always install child restraint systems prop-
erly, even if they are not being used. Make
sure that you observe the child restraint sys-
tem manufacturer's installation instructions.
You will find further information on stowingobjects, luggage or loads under "Loading guide-lines" (Ypage 239).
GWARNING
Child restraint systems or their securing sys-
tems which have been damaged or subjected
to a load in an accident can no longer protect
as intended. The child cannot then be
restrained in the event of an accident, heavy
braking or sudden changes of direction. There
is an increased risk of injury, possibly even
fatal.
Replace child restraint systems which have
been damaged or subjected to a load in an
accident as soon as possible. Have the secur-
ing systems on the child restraint system
checked at a qualified specialist workshop,
before you install a child restraint system
again.
The securing systems of child restraint systemsare:
Rthe seat belt system
Rthe LATCH-type (ISOFIX) securing rings
Rthe Top Tether anchorages
If it is absolutely necessary to carry a child onthe front-passenger seat, be sure to observe theinformation on the "Occupant ClassificationSystem (OCS)" (Ypage 47). There you will alsofind information on deactivating the front-passenger front air bag.
All child restraint systems must meet the fol-lowing standards:
RU.S. Federal Motor Vehicle Safety Standards213 and 225
RCanadian Motor Vehicle Safety Standards213 and 210.2
Confirmation that the child restraint system cor-responds to the standards can be found on aninstruction label on the child restraint system.This confirmation can also be found in the instal-lation instructions that are included with thechild restraint system.
Observe the warning labels in the vehicle inte-rior and on the child restraint system.
56Children in the vehicle
Safety

LATCH-type (ISOFIX) child seat secur-
ing system
GWARNING
For LATCH-type (ISOFIX) child restraint sys-
tems in which the child is secured using the
safety belt integrated in the child restraint
system, the maximum permissible weight of
the child and child restraint system together
is 73 lbs (33 kg).
If the child and the child restraint system
together weigh more than 73 lbs (33 kg), the
LATCH-type (ISOFIX) child restraint system
with integrated safety belt no longer offers
sufficient protection. The LATCH-type (ISO-
FIX) child seat securing system may be over-
loaded, and the child may not be restrained in
an accident, for example. This poses an
increased risk of injury or even fatal injury.
If the child and the child restraint system
together weigh more than 73 lbs(33 kg),use
only a LATCH-type (ISOFIX) child restraint sys-
tem in which the child is also secured with the
vehicle seat belt. Also secure the child
restraint system with the Top Tether belt, if
available.
Regularly check that the permissible grossweight of the child together with the childrestraint system is still maintained.
Always comply with the manufacturer's instal-lation and operating instructions for the childrestraint system used.
Before every trip, make sure that the LATCH-type (ISOFIX) child restraint system is engagedcorrectly in both LATCH-type (ISOFIX) securingrings
!When installing the child restraint system,make sure that the seat belt for the middleseat does not get trapped. The seat belt couldotherwise be damaged.
XInstall the LATCH-type (ISOFIX) child restraintsystem on both LATCH-type (ISOFIX) securingringsC.
LATCH-type (ISOFIX) is a standardized securingsystem for specially designed child restraintsystems on the rear seats. LATCH-type (ISOFIX)securing rings for two LATCH-type (ISOFIX) childrestraint systems are installed on the left andright of the rear seats.
Non-LATCH-type (ISOFIX) child seats may alsobe used and can be installed using the vehicle'sseat belt system. Install the child seat accordingto the manufacturer's instructions.
Top Tether
Introduction
Top Tether provides an additional connectionbetween the child restraint system secured witha LATCH-type (ISOFIX) system and the vehicle.This helps reduce the risk of injury even further.If the child restraint system is equipped with aTop Tether belt, this should always be used.
Important safety notes
GWARNING
If the rear seat backrests are not locked, they
could fold forwards in the event of an acci-
dent, heavy braking or sudden changes of
direction. As a result, child restraint systems
cannot perform their intended protective
function. Rear seat backrests that are not
locked can also cause additional injuries, e.g.
in the event of an accident. This poses an
increased risk of injury or even fatal injury.
Children in the vehicle57
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Always lock rear seat backrests after instal-
ling a Top Tether belt. Observe the lock veri-
fication indicator. Adjust the rear seat backr-
ests so that they are in an upright position.
If the rear backrest is not engaged and locked,the red lock verification indicator will be visible(Ypage 242).
Top Tether anchorages
The Top Tether anchorage points are installed inthe rear compartment behind the headrestraints on the parcel shelf.
XPress down the rear of coverDin the direc-tion of the arrow.CoverDis raised slightly at the front.
XFold coverDup.
Vehicles with adjustable head restraints:
XMove head restraintCup.
XRoute Top Tether belt