Mercedes-Benz A-CLASS SEDAN 2021 Seat Belts and Safety User Manual

Introduction

A wonderful car that blends style, performance, and cutting-edge safety technologies to deliver a safe and comfortable driving experience is the Mercedes-Benz A-Class Sedan 2021. The seat belt system is one of the most important safety features in this car because it protects occupants in the case of an accident or sudden halt. The A-Class Sedan is equipped with cutting-edge seat belt technology to offer the optimum level of protection for both the driver and passengers. Seat belts are a crucial component of any vehicle’s safety system. These seat belts are made to keep passengers secure in their seats during a collision, reducing the risk of injuries by preventing them from being flung forward or out of their seats. The seat belt system of the Mercedes-Benz A-Class Sedan 2021 includes a number of cutting-edge safety features. Pretensioners are one of these characteristics; they tighten the seat belts automatically to eliminate any slack in the case of a collision or emergency movement. By ensuring that passengers are held firmly in position, this feature improves the efficiency of seat belts.

The A-Class Sedan also has force limiters, which are intended to lessen the force that seat belts exert on occupants’ bodies. By regulating the amount of force applied by the seat belt system during a crash, this function helps to reduce the risk of chest and abdominal injuries. The A-Class Sedan also provides seat belt reminders for every position, making sure that both the driver and passengers are reminded to buckle up for their safety. In order to promote safe seat belt usage and reduce the risk of injury in the case of an accident, these reminders use visual and audible cues.
In conclusion, the Mercedes-Benz A-Class Sedan 2021’s seat belt system is a crucial safety component that puts occupant protection first. The seat belts in this car, with their cutting-edge technology and sophisticated design, make a substantial contribution to guaranteeing a comfortable and safe driving experience for everyone inside.

Seat belts

Protection provided by the seat belt
Always fasten your seat belt correctly before starting a journey. A seat belt can only provide the best level of protection if it is worn correctly.

WARNING
Risk of injury or death due to incorrectly fastened seat belt

If the seat belt is not worn correctly, it cannot perform its intended protective function.
In addition, an incorrectly fastened seat belt can also cause injuries, for example, in the event of an accident or when braking or changing direction suddenly.
Always ensure that all vehicle occu‐pants have their seat belts fastened correctly and are sitting properly.
Always observe the instructions about the correct driver’s seat position and adjusting the seat.

In order for the correctly worn seat belt to provide the intended level of protection, each vehi‐cle occupant must observe the following infor‐mation:

1. The seat belt must not be twisted and must fit tightly and snugly across the body.
2. The seat belt must be routed across the center of the shoulder and as low down across the hips as possible.
3. The shoulder section of the seat belt should not touch your neck nor be routed under your arm or behind your back.
4. Avoid wearing bulky clothing, e.g. a winter coat.
5. Push the lap belt down as far as possible across your hips and pull tight with the shoulder section of the belt. Never route the lap belt across your abdomen.
   Pregnant women must also take particular care with this.
6. Never route the seat belt across sharp, pointed, abrasive or fragile objects.
7. Only one person should use each seat belt at any one time. Never allow babies and children to travel sitting on the lap of another vehicle occupant.
8. Never secure objects with a seat belt if the seat belt is also being used by one of the vehicle’s occupants. Always observe the instructions for loading the vehicle when securing objects, luggage or loads.
   Also ensure that no objects, e.g. a cushion, are ever placed between a person and the seat.

The seat belts on the following seats are equipped with a special seat belt retractor:

1. Front passenger seat
2. Rear seats

Activate or deactivate the special seatbelt retractor.
If children are traveling in the vehicle, be sure to observe the instructions and safety notes on “Children in the vehicle”.

Limitations of the protection provided by the seat belt

WARNING
Risk of injury or death due to an incorrect seat position

The seat belt does not offer the intended level of protection if you have not moved the seat backrest to an almost vertical position.
You could slip beneath the seat belt and injure yourself.

1. Adjust the seat properly before commencing your journey.
2. Always ensure that the seat backrest is in an almost vertical position and that the shoulder belt is routed across the center of your shoulder.

WARNING
Risk of injury or death when additional restraint systems are not used for persons with a smaller stature.
Persons under 5 ft (1.50 m ) tall cannot wear the seat belt correctly without a suitable additional restraint system.

1. Always secure persons under 5 ft (1.50 m) tall in a suitable restraint system.

WARNING
Risk of injury or death due to damaged or modified seat belts

Seat belts cannot provide protection in the following situations:

1. The seat belt is damaged, has been modified, is extremely dirty, bleached or dyed
2. The seat belt buckle is damaged or extremely dirty
3. Modifications have been made to the Emergency Tensioning Device, seat belt anchorage or seat belt retractor

Seat belts may sustain non-visible damage in an accident, e.g. due to glass splinters.
Modified or damaged seat belts could tear or fail in the event of an accident, for example.
Modified Emergency Tensioning Devices could accidentally trigger or fail to function as intended.

1. Never modify the seat belt system, for example the seat belt, seat belt buckle, Emergency Tensioning Device, seat belt anchorage and seat belt retractor.
2. Make sure that the seat belts are undamaged, not worn and clean.
3. Always have the seat belts checked immediately after an accident at a qualified specialist workshop.

Only use seat belts which have been approved for your vehicle by Mercedes-Benz.

WARNING
Risk of injury or death from deployed pyrotechnic Emergency Ten‐sioning Devices.

Pyrotechnic Emergency Tensioning Devices that have been deployed are no longer opera‐tional and are unable to perform their inten‐ded protective function.
Therefore, have deployed pyrotechnic Emergency Tensioning Devices immedi‐ately replaced at a qualified specialist workshop.
Mercedes-Benz recommends that you have the vehicle towed to a qualified specialist workshop after an accident.

NOTE
Damage caused by trapping the seat belt

If an unused seat belt is not fully retracted, it may become trapped in the door or in the seat mechanism.
Always ensure that an unused seat belt is fully retracted.

Fastening seat belts
If the seat belt is pulled quickly or sharply, the seat belt retractor locks. The seat belt strap cannot be pulled out any further.

Always engage seat belt tongue 2 of the seat belt into the seat belt buckle 1 of the corresponding seat.

Vehicles with automatic front passenger air‐bag shutoff:

NOTE
Deployment of the Emergency Tensioning Device and side airbag when the front passenger seat is unoccupied

If the seat belt tongue is engaged in the seat belt buckle of the unoccupied front passenger seat, the Emergency Tensioning Device and the side air bag may also deploy in the event of an accident along with other systems.

Vehicles without automatic front passenger airbag shutoff:

NOTE
Deployment of the Emergency Tensioning Device when the front-passenger seat is unoccupied

If the seat belt tongue is engaged in the seat belt buckle of the unoccupied front-passenger seat, the Emergency Tensioning Device may also deploy in the event of an accident along with other systems.

Seat belt adjustment function
Vehicles with PRE-SAFE®: After a front seat belt has been fastened, the automatic seat belt adjustment may apply a certain tightening force. Do not hold the seat belt tightly while it is adjusting.
You can activate and deactivate the seat belt adjustment function using the multimedia system.

Activating/deactivating seat belt adjustment via the multimedia system

Multimedia system:
4© 5 Settings 5 Vehicle
Activate or deactivate Belt Adjustment.

Releasing seat belts
Press the release button in the seat belt buckle and guide the seat belt back with the seat belt tongue.

Seat belt warning function for the driver and front passenger
The seat belt warning lamp in the instrument display is a reminder that all vehicle occupants must wear their seat belts correctly.
The  seat belt warning lamp lights up for six seconds every time the vehicle is started.
In addition, a warning tone may sound.
When the driver’s and front passenger’s doors are closed and the driver and front passenger have fastened their seat belts, the seat belt warning goes out.

In the following cases, the seat belt warning lights up during a journey if:

1. The vehicle speed exceeds 15 mph (25 km/h) and the driver’s or front passenger seat belt is not fastened.
2. The driver or front passenger unfastens their seat belt while the vehicle is in motion.

Airbags

Overview of airbags

1. Driver’s knee airbag
2. Driver’s airbag
3. Front passenger airbag
4. Front passenger knee airbag
5. Window curtain airbag
6. Side airbag

The installation location of an airbag is identified by the AIRBAG symbol.
When enabled, an airbag can provide additional protection for the respective vehicle occupant. Potential protection provided by each airbag:

1. Knee airbag: thigh, knee and lower leg
2. Driver’s airbag, front passenger airbag: head and ribcage
3. Window curtain airbag: head
4. Side airbag: ribcage and pelvis

NOTE
Mercedes-AMG vehicles
Observe the notes in the Supplement. You could otherwise fail to recognize dangers.

WARNING
Risk of injury or death if the co-driver airbag is enabled
If the co-driver airbag is enabled, a child on the co-driver seat may be struck by the co-driver airbag during an accident.

NEVER use a rearward-facing child restraint system on a seat with an ENABLED FRONT AIRBAG; DEATH or SERIOUS INJURY to the CHILD can occur.
When installing a child restraint system on the front passenger seat, observe the vehicle-specific information. Also, always observe the notes on rearward-facing or forward-facing child restraint systems on the front passenger seat.

Information on automatic front passenger airbag shutoff
The front passenger airbag can only be deployed in an accident if the PASSENGER AIR BAG OFF indicator lamp is off. If the front passenger seat is occupied, make sure, both before and during the journey, that the status of the front passenger airbag is correct.

NOTE
Important points to remember if the front passenger seat is unoccupied

In an accident, the components of the restraint system may deploy unnecessarily on the front passenger side if:

1. There are heavy objects on the front passenger seat.
2. The seat belt tongue is engaged in the seat belt buckle of the front passenger seat and the front passenger seat is unoccupied.
3. Stow objects in a suitable place.
4. Only one person should use each seat belt at any one time.

Depending on the detected accident situation, the window curtain airbag on the front passenger side may deploy. The airbag is deployed regardless of whether the front passenger seat is occupied.

Protective capacity of the airbags
Depending on the accident situation, an airbag may supplement the protection offered by a cor‐rectly fastened seat belt.

WARNING
Risk of injury or death due to an incorrect seat position
If you deviate from the correct seat position, the airbag cannot perform its intended pro‐tective function.

Each vehicle occupant must make sure of the following:

1. Fasten seat belts correctly. Pregnant women must take particular care to ensure that the lap belt never lies across the abdomen.
2. Adopt the correct seat position and keep as far away as possible from the airbags.
3. Observe the following information.
4. Always make sure that there are no objects between the airbag and vehicle occupant.

To avoid the risks resulting from the deployment of an airbag, each vehicle occupant must observe the following information in particular:

1. Before starting your journey, adjust your seat correctly; the driver’s seat and front passenger seat should be moved as far back as possible.
   When doing so, always observe the information on the correct driver’s seat position (/ page 87).
2. Only hold the steering wheel by the steering wheel rim. This allows the airbag to be fully deployed.
3. Always lean against the seat backrest when the vehicle is in motion. Do not lean forwards or against the door or side window. You may otherwise be in the deployment area of the airbags.
4. The occupants must always keep their feet on the floor. Do not put your feet on the cockpit, for example. Your feet may other‐wise be in the deployment area of the airbag.
5. If children are traveling in the vehicle, observe the additional notes.
6. Always store and secure objects correctly.

Objects in the vehicle interior may prevent an airbag from functioning correctly. Each vehicle occupant must always make sure of the follow‐ing in particular:

1. There are no people, animals or objects between the vehicle occupants and an airbag.
2. There are no objects between the seat, door and door pillar (B-pillar).
3. There are no hard objects, e.g. coat hangers, hanging on the grab handles or coat hooks.
4. There are no accessory parts, such as mobile navigation devices, mobile phones or cup holders, within the deployment area of an air‐bag, e.g. on the cockpit, on the door, on the side window or on the side trim.
5. In addition, no connecting cables, tensioning straps or retaining straps must be routed or attached to the vehicle within the deployment area of an airbag. Always comply with the accessory manufacturer’s installation instructions and, in particular, the notes on suitable places for installation.
6. There are no heavy, sharp-edged or fragile objects in the pockets of your clothing. Store such objects in a suitable place.

Limited protection provided by airbags

WARNING
Risk of injury due to modifications to the cover of an airbag

If you modify the cover of an airbag or affix objects such as stickers to it, the airbag may no longer function correctly.
Never modify the cover of an airbag and do not affix objects to it.
The installation location of an airbag is identified by the AIRBAG symbol

WARNING
Risk of injury or death due to the use of unsuitable seat covers.
Due to unsuitable seat covers, the airbags cannot protect vehicle occupants as intended.

In addition, the operation of the automatic front passenger airbag shutoff could be restricted.
You should only use seat covers that have been approved for the correspond‐ing seats by Mercedes-Benz.

The function of the airbags can be impaired due to modifications or incorrect work per‐formed on the doors or door trim, or if the doors are damaged.

1. Never modify the doors or parts of the doors.
2. Always have work on the doors or door trim carried out at a qualified specialist workshop.

Status of the front passenger front airbag

Function of the automatic front passenger airbag shutoff
The automatic front passenger airbag shutoff is able to detect whether the front passenger seat is occupied by a person or a child restraint sys‐tem. The front passenger airbag and front passenger knee airbag are enabled or disabled accordingly.

WARNING
Risk of injury or death due to objects under the co-driver seat
Objects trapped under the co-driver seat can interfere with the function of the automatic co-driver airbag shutoff or damage the system.

1. Do not store any objects under the codriver seat.
2. When the co-driver seat is occupied, make sure that no objects are trapped under the co-driver seat.

When installing a child restraint system on the front passenger seat, always make sure of the following:

1. Ensure that the child restraint system is positioned correctly.
2. Always comply with the child restraint system manufacturer’s installation instructions.
3. Never place objects (e.g. cushions) under or behind the child restraint system.
4. Fully retract the seat cushion length adjustment.
5. The entire base of the child restraint system must always rest on the sitting surface of the front passenger seat.
6. The backrest of the forward-facing child restraint system must, as far as possible, be resting on the seat backrest of the front passenger seat.
7. The child restraint system must not touch the roof or be put under strain by the head restraints. Adjust the seat backrest inclination and the head restraint setting accordingly.

WARNING
Risk of injury or death due to objects between the seat surface and the child restraint system
Objects between the sitting surface and the child restraint system could affect the function of the automatic co-driver airbag shut‐off.

1. Do not place any objects between the sitting surface and the child restraint system.
2. The entire base of the child restraint system must always rest on the sitting surface of the co-driver seat.
3. The backrest of the forward-facing child restraint system must, as far as possible, be resting on the seat backrest of the co-driver seat.
4. Always comply with the child restraint system manufacturer’s installation instructions.

A person on the front passenger seat must observe the following information:

1. Fasten seat belts correctly.
2. Sit in an almost upright seat position with their back against the seat backrest.
3. Sit with their feet resting on the floor, if possible.

The front passenger airbag may otherwise be disabled by mistake, for example, in the follow‐ing situations:

1. The front passenger transfers their weight by supporting themselves on a vehicle armrest.
2. The front passenger sits in such a way that their weight is raised from the sitting sur‐face.

WARNING
Risk of injury or death due to a disabled front passenger airbag
The front passenger airbag is disabled when the PASSENGER AIR BAG OFF indicator lamp is lit.
A person in the front passenger seat could then, for example, come into contact with the vehicle interior, especially if the person is sitting too close to the cockpit.

If the front passenger seat is occupied, always ensure that:

1. The classification of the person in the front passenger seat is correct and the front passenger airbag is enabled or disa‐bled in accordance with the person in the front passenger seat.
2. The front passenger seat has been moved as far back as possible.
3. The person is seated correctly.
4. Both before and during the journey, ensure that the status of the front passenger airbag is correct.

If the front passenger seat is occupied, the clas‐sification of the person or child restraint system on the front passenger seat takes place after the front passenger airbag shutoff self-test. The PASSENGER AIR BAG indicator lamps display the status of the front passenger airbag. Always observe the notes on the function of the PASSENGER AIR BAG indicator lamps.

The function of the PASSENGER AIR BAG indicator lamps

Self-test of automatic front passenger airbag shutoff
When the ignition is switched on, a self-test is performed during which the two PASSENGER AIR BAG ON and OFF indicator lamps light up simultaneously.

The status of the front passenger airbag is displayed via the PASSENGER AIR BAG indicator lamps after the self-test:

1. ON is lit: the front passenger airbag may deploy during an accident.
   The indicator lamp goes out after approximately 60 seconds.
2. ON and OFF are not lit: the front passenger airbag may deploy during an accident.
3. OFF is lit: the front passenger airbag is disabled. It will then not be deployed in the event of an accident.

If the PASSENGER AIR BAG ON indicator lamp is off, only the PASSENGER AIR BAG OFF indicator lamp shows the status of the front passenger airbag. The PASSENGER AIR BAG OFF indicator lamp may be lit continuously or be off. If the PASSENGER AIR BAG OFF indicator lamp and the restraint system warning lamp light up simultaneously, the front passenger seat may not be used. Also in this case, do not install a child restraint system on the front passenger seat. Have the automatic front passenger airbag shutoff checked and repaired immediately at a qualified specialist workshop.

Status display
If the front passenger seat is occupied, ensure, both before and during the journey, that the status of the front passenger airbag is correct for the current situation.
After installing a rearward-facing child restraint system on the front passenger seat: the PASSENGER AIR BAG OFF must be lit continuously.

WARNING
Risk of injury or death when using a rearward-facing child restraint system while the front passenger airbag is enabled.

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 airbag can deploy in the event of an accident. The child could be struck by the airbag. Always ensure that the front passenger air‐bag is disabled. The PASSENGER AIR BAG OFF indicator lamp must be lit.
NEVER use a rearward-facing child restraint system on a seat with an ENABLED FRONT AIRBAG; DEATH or SERIOUS INJURY to the CHILD can occur.

When installing a child restraint system on the front passenger seat, observe the vehicle-specific information.
Depending on the child restraint system and the stature of the child, the PASSENGER AIR BAG OFF indicator lamp may be off. In this case, do not install the rearward-facing child restraint system on the front passenger seat. Instead, install the rearward-facing child restraint system on a suitable rear seat.

After installing a forward-facing child restraint system on the front passenger seat:
depending on the child restraint system and the stature of the child, the PASSENGER AIR BAG OFF may be lit continuously or be off. Always observe the following information.

WARNING
Risk of injury or death due to incorrect positioning of the forward-facing child restraint system.
If you secure a child in a forward-facing child restraint system on the front passenger seat that is positioned too close to the cockpit, in the event of an accident, the child could:

1. come into contact with parts of the vehicle’s interior if the PASSENGER AIR BAG OFF indicator lamp is lit, for example
2. be struck by the airbag if the PASSENGER AIR BAG OFF indicator lamp is off
3. Always move the front passenger seat as far back as possible and fully retract the seat cushion length adjustment. While doing so, always make sure that the shoulder belt strap is correctly routed from the seat belt outlet of the vehicle to the shoulder belt guide on the child restraint system. The shoulder belt strap must be routed forwards and downwards from the seat belt outlet. If necessary, adjust the front passenger seat accordingly.
4. Always comply with the child restraint system manufacturer’s installation instructions.

When installing a child restraint system on the front passenger seat, observe the vehicle-spe‐cific information (/ page 61).

If a person is sitting in the front passenger seat:
PASSENGER AIR BAG OFF may be lit continuously or be off, depending on the person’s stature.
A person on the front passenger seat must always observe the following information:

1. If the front passenger seat is occupied by an adult or a person with a stature corresponding to that of an adult, the PASSENGER AIR BAG OFF indicator lamp must be off. This indicates that the front passenger airbag is enabled.
   If the PASSENGER AIR BAG OFF indicator lamp is lit continuously, an adult or person with a build corresponding to that of an adult should not use the front passenger seat.
   Instead, they should use a rear seat.
2. If the front passenger seat is occupied by a person of smaller stature (e.g. a teenager or small adult), the PASSENGER AIR BAG OFF indicator lamp either lights up continuously or remains off, depending on the classification.
   1. If the PASSENGER AIR BAG OFF indicator lamp is off: move the front passenger seat as far back as possible, or the per‐son of smaller stature should use a rear seat.
   2. If the PASSENGER AIR BAG OFF indicator lamp is lit continuously: a person of smaller stature should not use the front passenger seat.

WARNING
Risk of injury or death when the PASSENGER AIR BAG OFF indicator lamp is lit.

If the PASSENGER AIR BAG OFF indicator lamp remains lit after the self-test, the front passenger airbag is disabled.
If the front passenger seat is occupied, always ensure that:

1. The classification of the person in the front passenger seat is correct and the front passenger airbag is enabled or disa‐bled in accordance with the person in the front passenger seat.
2. The person is seated properly with a correctly fastened seat belt.

Be sure to also observe the following further related subjects:

1. Child restraint system on the front passenger seat.

PRE-SAFE® system

PRE-SAFE® (anticipatory occupant protection)
PRE-SAFE® is able to detect certain critical driving situations and implement pre-emptive measures to protect the vehicle occupants.

PRE-SAFE® can implement the following measures independently of each other:

1. Tightening the seat belts on the driver’s seat and front passenger seat.
2. Closing the side windows.
3. Vehicles with sliding sunroof: Close the sliding sunroof.
4. Vehicles with memory function: Move the front passenger seat to a more favorable seat position.
5. PRE-SAFE® Sound: provided that the multimedia system is switched on, generates a brief noise signal to stimulate the innate protective mechanism of a person’s hearing.

The automatic adjustment of the seat posi‐tion may result in damage to the seat and/or the object.
Stow objects in a suitable place.

Reversing the PRE-SAFE® system measures
If an accident did not occur, the pre-emptive measures that were taken are reversed.
You will need to perform certain settings your‐self.

1. If the seat belt pre-tensioning is not reduced, move the seat backrest back slightly. The locking mechanism releases.

Function of PRE-SAFE® PLUS (anticipatory occupant protection plus)
PRE-SAFE® PLUS can detect certain impacts, particularly an imminent rear impact, and take pre-emptive measures to protect the vehicle occupants. These measures cannot necessarily prevent an imminent impact.

PRE-SAFE® PLUS can implement the following measures independently of each other:

1. Tightening the seat belts on the driver’s seat and front passenger seat.
2. Increasing brake pressure when the vehicle is stationary. This brake application is canceled automatically when the vehicle pulls away.

If an accident did not occur, the pre-emptive measures that were taken are reversed.

System limits
The system will not initiate any action in the fol‐lowing situations:

1. When backing up
   The system will not initiate any braking applica‐tion in the following situations:
2. Whilst driving
3. When entering or exiting a parking space while using Active Parking Assist

Automatic measures after an accident

Depending on the type and severity of the acci‐dent, and depending on the vehicle’s equipment, the following measures can be implemented, for example:

1. Automatic braking (post-collision brake)
2. Activating the hazard warning lights
3. Triggering an automatic emergency call.
4. Switching off the engine
   To restart the vehicle, switch the ignition off and switch it back on. Depending on the type and severity of the accident, it is possible that the vehicle can no longer be started.
5. Switching off the fuel supply
6. Unlocking the vehicle doors
7. Lowering the side windows
8. Displaying the emergency guide in the multi-media system display
9. Switching on the interior lighting

The function of the post-collision brake
Depending on the accident situation, the post-collision brake can minimize the severity of a fur‐ther collision or even avoid it.
If an accident is detected, the post-collision brake can implement automatic braking. When the vehicle has come to a standstill, the electric parking brake is automatically applied.

The driver can cancel automatic braking by tak‐ing the following actions:

1. Braking more strongly than automatic braking
2. Fully depressing the accelerator pedal with force

Safely transporting children in the vehicle

Always observe when children are traveling in the vehicle
Also strictly observe the safety notes for the specific situation. In this way you can recognize potential risks and avoid dangers if chil‐dren are traveling in the vehicle.

Be diligent
Bear in mind that negligence when securing a child in the child restraint system may have seri‐ous consequences. Always be diligent in securing a child carefully before every journey.
To improve protection for children younger than 12 years old or under 5 ft (1.50 m) in height, Mercedes-Benz recommends you observe the following information:

1. Always secure the child in a child restraint system suitable for this Mercedes-Benz vehicle.
2. The child restraint system must be appropriate to the age, weight and size of the child.
3. The vehicle seat must be suitable for installing a child restraint system.
   Accident statistics show that children secured on the rear seats are generally safer than children secured on the front seats. For this reason, Mercedes-Benz strongly advises that you install a child restraint system on a rear seat.

The generic term child restraint system
The generic term child restraint system is used in this Operator’s Manual. A child restraint system is, for example:

1. A baby car seat
2. A rearward-facing child seat
3. A forward-facing child seat
4. A child booster seat with a backrest and seat belt guide
   Mercedes-Benz recommends using a child booster seat with a backrest.

The child restraint system must be appropriate to the age, weight and size of the child.

Observe laws and legal requirements
Always observe the legal requirements when using a child restraint system in the vehicle.

Observe standards for child restraint systems
All child restraint systems must meet the follow‐ing standards:

1. U.S. Federal Motor Vehicle Safety Standards 213 and 225
2. Canadian Motor Vehicle Safety Standards 213 and 210.2
   Confirmation that the child restraint system complies with the standards can be found on an instruction label on the child restraint system. This confirmation can also be found in the instal‐lation instructions that are included with the child restraint system.

Detecting risks, avoiding danger
Securing systems for child restraint systems in the vehicle
Only use the following securing systems for child restraint systems:

1. The LATCH-type (ISOFIX) securing rings
2. The vehicle’s seat belt system
3. The Top Tether anchorages
   Installing a LATCH-type (ISOFIX) child restraint system is favored.
   Simply attaching to the securing rings on the vehicle can reduce the risk of installing the child restraint system incorrectly.
   When securing a child with the integrated seat belt of the LATCH-type (ISOFIX) child restraint system, always comply with the permissible gross weight for the child and child restraint sys‐tem (/ page 56).
   A booster seat may be necessary to achieve proper seat belt positioning for children over 40 lbs (18 kg) in weight or until they reach a height where a three-point seat belt can be installed properly without a booster seat. Mercedes-Benz recommends a suitable child booster seat with a backrest and seat belt guide.

Advantages of a rearward-facing child restraint system
It is preferable to transport a baby or a small child in a suitable rearward-facing child restraint system. In this case, the child sits in the oppo‐site direction to the direction of travel and faces backwards.
Babies and small children have comparatively weak neck muscles in relation to the size and weight of their head. The risk of injury to the cer‐vical spine during an accident can be reduced in a rearward-facing child restraint system.

Always secure a child restraint system correctly
The child can then not be protected or restrained as intended.

1. Be sure to comply with the manufactur‐er’s installation instructions for the child restraint system and its correct use.
2. Make sure that the entire base of the child restraint system always rests on the sitting surface of the seat.
3. Never place objects (e.g. cushions) under or behind the child restraint sys‐tem.
4. Use child restraint systems only with the original cover designed for them.
5. Always replace damaged covers with genuine covers.

WARNING
Risk of injury or death due to unsecured child restraint systems in the vehicle

If the child restraint system is incorrectly installed or not secured, it can come loose.
The child restraint system could be flung around and hit vehicle occupants.

1. Always install child restraint systems correctly, even when not in use.
2. Always comply with the child restraint system manufacturer’s installation instructions.
3. Always observe the child restraint system manufacturer’s installation and operating instructions as well as the vehicle-specific information:
   1. Installing the LATCH-type (ISOFIX) child restraint system on the rear seat.
   2. Securing the child restraint system with the seat belt on the rear seat.
   3. Securing the child restraint system with the seat belt on the front passenger seat. Observe the specific instructions for the rearward-facing and forward-facing child restraint systems.
      If the front passenger seat is occupied, ensure, both before and during the journey, that the status of the front passenger airbag is correct for the cur‐rent situation.
4. Observe the warning labels in the vehicle interior and on the child restraint system.
5. Also, secure Top Tether if present.

Do not modify the child restraint system

WARNING
Risk of injury due to modifications to the child restraint system
The child restraint system can no longer function properly. This poses an increased risk of injury.

1. Never modify a child restraint system.
2. Only affix accessories that have been specially approved for this child restraint system by the child restraint system’s manufacturer.

Only use child restraint systems that are in proper working condition
Child restraint systems or their retaining sys‐tems that have been subjected to stress in an accident may not be able to perform their intended protective function.
It may be the case that the child cannot be properly restrained.

1. Always immediately replace child restraint systems that have been dam‐aged or involved in an accident.
2. Have the securing systems for the child restraint systems checked at a qualified specialist workshop before installing a child restraint system again.

WARNING
Risk of burns when the child seat is exposed to direct sunlight
If the child restraint system is exposed to direct sunlight or heat, parts could heat up.
Children could suffer burns from these parts, particularly on the metallic parts of the child restraint system.

1. Always make sure that the child restraint system is not exposed to direct sunlight.
2. Protect the child restraint system, e.g. with a blanket.
3. If the child restraint system has been exposed to direct sunlight, allow it to cool before securing a child in it.
4. Never leave children unattended in the vehicle.

Observe when stopping or parking

WARNING
Risk of accident and injury due to children left unattended in the vehicle

If children are left unsupervised in the vehi‐cle, they could, in particular:

1. Open doors, thereby endangering other persons or road users.
2. Get out and be struck by oncoming traffic.
3. Operate vehicle equipment and become trapped, for example.

In addition, the children could also set the vehicle in motion, for example by:

1. Releasing the parking brake.
2. Changing the transmission position.
3. Starting the vehicle.
4. Never leave children unattended in the vehicle.
5. When leaving the vehicle, always take the SmartKey with you and lock the vehicle.
6. Keep the vehicle SmartKey out of reach of children.

WARNING
Danger to life due to exposure to extreme heat or cold in the vehicle
If people, particularly children, are exposed to extreme temperatures over an extended period of time, there is a risk of serious injury or danger to life.

Activating or deactivating the special seal belt retractor of the seat belt

WARNING
Risk of injury or death if a seat belt is unfastened while the vehicle is in motion
If the seat belt is released while the vehicle is in motion, the child safety lock is deactivated and the child restraint system is no longer correctly secured. The seat belt is drawn in slightly by the inertia reel and cannot be immediately closed again.

1. Stop the vehicle immediately in accordance with the traffic conditions.
2. Activate the special seal belt retractor again and correctly secure the child restraint system.

When enabled, the special seal belt retractor ensures that the seat belts of the front passenger seat and rear seats do not slacken once the child restraint system is secured.

The seat belts on the following seats are equip‐ped with a special seal belt retractor:

1. Front passenger seat
2. Rear seats
3. To install a child restraint system: when installing a child restraint system, always observe the manufacturer’s installation and operating instructions as well as the informa‐tion in this Operator’s Manual.
4. Pull the seat belt smoothly from the seat belt outlet.
5. Engage the seat belt tongue in the seat belt buckle.
6. To activate the special seal belt retrac‐tor: pull the seat belt out fully and let the inertia reel retract it again.
7. When the special seal belt retractor is activa‐ted, you will hear a ratcheting sound.
8. Push the child restraint system down until the seat belt sits tightly.
9. To deactivate the special seal belt retrac‐tor: press the release button of the seat belt buckle.
10. Hold the seat belt tongue and guide back to the seat belt outlet.

Installing a LATCH-type (ISOFIX) child restraint system on the rear seat

WARNING
Risk of accident if the rear bench seat, rear seat and seat backrest are not engaged
The rear bench seat, rear seat and seat backrest may fold forwards, even when you are driving.

1. As a result, the vehicle occupant will be pushed into the seat belt with increased force. The seat belt will not be able to protect as intended and could cause additional injury.
2. Objects or loads in the trunk or cargo compartment will not be restrained by the seat backrest.
3. Make sure that the rear bench seat, the rear seat and the seat backrest are engaged before every trip.

If the rear seat backrest is not engaged and locked in place, the red lock verification indicator will be visible.
The LATCH-type (ISOFIX) child seat securing systems may be overloaded and the child may not be restrained in the event of an accident, for example.

1. If the child and the child restraint system together weigh more than the permissible gross mass of 73 lb (33 kg), use only a LATCH-type (ISOFIX) child restraint system that secures the child with the vehicle seat belt.
2. Also secure the child restraint system with the Top Tether belt, if available.
3. Always comply with the information about the mass of the child restraint system:
   R In the manufacturer’s installation and operating instructions for the child restraint system used
4. R On a label on the child restraint system, if present
   Regularly check that the permissible gross mass of the child and child restraint system is still complied with.

When installing a child restraint system, observe the following:

1. Always observe the correct use of the seats and consider their suitability for attaching a child restraint system.
2. Always comply with the manufacturer’s installation and operating instructions for the child restraint system used.
3. Make sure that the child’s feet do not touch the front seat. If necessary, move the front seat slightly forwards.
4. When installing a LATCH-type (ISOFIX) child restraint system, also observe the follow‐ing:
5. When using a baby car seat in weight group 0/0+ and a rearward-facing child restraint system in weight group I on a rear seat: adjust the front seat so that the seat does not touch the child restraint sys‐tem.
6. When using a forward-facing child restraint system in weight group I: remove the head restraint from the respec‐tive seat, if possible. In addition, the back‐rest of the child restraint system must lie as flat as possible against the backrest of the vehicle seat.
   After the child restraint system has been removed, replace the head restraints again immediately and adjust them correctly.
7. If the head restraint of the child seat cannot be fully extended when it is installed in the vehicle, this will result in restrictions on the maximum size setting for child restraint sys‐tems in weight category II or III.
   Contact with the roof when the head restraint is fully extended and locked in place will not result in any restrictions on use.
8. The child restraint system must not be put under strain between the roof and the seat cushion and/or be installed facing the wrong direction. Where possible, adjust the seat cushion inclination accordingly.
9. The child restraint system must not be put under strain by the head restraint. Adjust the head restraints as appropriate.

LATCH-type (ISOFIX) mounting bracket
Before every journey, make sure that the LATCH-type (ISOFIX) child restraint system is engaged correctly in both mounting brackets in the vehi‐cle.

NOTE
Damage to the seat belt for the center seat during the installation of the child restraint system
Attach the LATCH-type (ISOFIX) child restraint system to both mounting brackets in the vehicle.

Securing Top Tether
WARNING
Risk of injury or death if the rear seat backrests are not locked after Top Tether belts are installed

The rear seat backrests may fold forwards when you are driving.
As a result, child restraint systems will no longer be able to perform their intended protective function. This may also cause additional injuries.

1. Always lock the rear seat backrests after installing Top Tether belts.
2. Observe the lock verification indicator.

If the rear seat backrest is not engaged and locked in place, the red lock verification indicator will be visible.

If the child restraint system is equipped with a Top Tether belt:
The risk of injury may be reduced by Top Tether. The Top Tether belt enables an additional connection between the child restraint system attached to LATCH-type (ISOFIX) and the vehicle.

Vehicles with adjustable head restraints:

1. If necessary, slide head restraint 1 upwards.
   
2. Guide Top Tether belt 4 under head restraint 1 between the two head restraint bars.

Vehicles without adjustable head restraints:

1. Top Tether belt with one seat belt strap: guide Top Tether belt 4 over the center of head restraint 1.
2. Top Tether belt with two seat belt straps: guide one Top Tether belt 4 past head restraint 1 on the right and left sides respectively.

All vehicles:

1. Install the LATCH-type (ISOFIX) child restraint system with Top Tether. In doing so, comply with the child restraint system manufacturer’s installation instructions.
2. Hook Top Tether hook 5 of Top Tether belt 4 into Top Tether anchorage 3 without twisting.
3. Tension Top Tether belt 4. In doing so, comply with the child restraint system manufacturer’s installation instructions.
4. Fold down cover 2 of Top Tether anchorage

Vehicles with adjustable head restraints:

1. If necessary, slide head restraint 1 downwards (/ page 92). Make sure that you do not interfere with the correct routing of Top Tether belt 4.

Securing the child restraint system with the seat belt

WARNING
Risk of accident if the rear bench seat, rear seat and seat backrest are not engaged
The rear bench seat, rear seat and seat back‐rest may fold forwards, even when you are driving.

1. As a result, the vehicle occupant will be pushed into the seat belt with increased force. The seat belt will not be able to protect as intended and could cause additional injury.
2. Objects or loads in the trunk or cargo compartment will not be restrained by the seat backrest.
3. Make sure that the rear bench seat, the rear seat and the seat backrest are engaged before every trip.

If the rear seat backrest is not engaged and locked in place, the red lock verification indica‐tor will be visible.

When installing a belt-secured child restraint system, observe the following:

1. Always comply with the manufacturer’s installation and operating instructions for the child restraint system used.
2. When using a weight category 0/0+ baby car seat and a weight category I rearward-facing child restraint system on a rear seat: adjust the front seat so that the seat does not touch the child restraint system.
3. When using a weight category I forward- facing child restraint system: remove the head restraint from the respective seat, if possible.
   After the child restraint system has been removed, replace the head restraints again immediately and adjust them correctly.
4. The backrest of the forward-facing child restraint system must, as far as possible, be resting on the seat backrest of the rear seat.
5. If the head restraint of the child seat cannot be fully extended when it is installed in the vehicle, this will result in restrictions on the maximum size setting for child restraint sys‐tems in weight category II or III.
   Contact with the roof when the head restraint is fully extended and locked in place will not result in any restrictions on use.
6. The child restraint system must not be put under strain between the roof and the seat cushion and/or be installed facing the wrong direction. Where possible, adjust the seat cushion inclination accordingly.
7. The child restraint system must not be put under strain by the head restraint. Adjust the head restraints as appropriate.
8. Make sure that the child’s feet do not touch the front seat. If necessary, move the front seat slightly forwards.

The seat belts on the following seats are equipped with a special seat belt retractor:

1. Front passenger seat
2. Rear seats

When enabled, the special seat belt retractor ensures that the seat belts of the front passenger seat and rear seats do not slacken once the child restraint system is secured.

1. Install the child restraint system.
   The entire base of the child restraint system must always rest on the sitting surface of the rear seat.
2. Always make sure that the shoulder belt strap is correctly routed from the seat belt outlet of the vehicle to the shoulder belt guide on the child restraint system.
   The shoulder belt strap must be routed for‐wards and downwards from the seat belt out‐let.

Notes on rearward-facing and forward-facing child restraint systems on the front passenger seat

WARNING
Risk of injury or death when using a rearward-facing child restraint system while the front passenger airbag is enabled

If you secure a child in a rearward-facing child restraint system on the front passenger seat and the PASSENGER AIR BAG OFF indi‐cator lamp is off, the front passenger airbag can deploy in the event of an accident. The child could be struck by the airbag. Always ensure that the front passenger air‐bag is disabled. The PASSENGER AIR BAG OFF indicator lamp must be lit.
NEVER use a rearward-facing child restraint system on a seat with an ENABLED FRONT AIRBAG; DEATH or SERIOUS INJURY to the CHILD can occur.
Observe the specific instructions for the rear‐ward-facing and forward-facing child restraint systems.

Always observe the status of the front passenger airbag on the PASSENGER AIR BAG OFF indica‐tor lamp:

1. When using a rearward-facing child restraint system on the front passenger seat, the front passenger airbag must always be disabled. This is only the case if the PASSENGER AIR BAG OFF indicator lamp is lit continuously.
2. If the PASSENGER AIR BAG OFF indicator lamp is off, the front passenger airbag is ena‐bled. The front passenger airbag may deploy during an accident.

Securing the child restraint system with the seat belt on the front passenger seat
When installing a belt-secured child restraint system on the front passenger seat, always observe the following:

1. Observe the notes on rearward-facing and forward-facing child restraint systems on the front passenger seat.
2. Observe the child restraint system manufacturer’s installation and operating instruc‐tions.
3. When using a forward-facing child restraint system in weight category I: remove the head restraint from the respective seat, if possible.
   After the child restraint system has been removed, replace the head restraints again immediately and adjust them correctly.
4. The backrest of the forward-facing child restraint system must, as far as possible, be resting on the seat backrest of the front passenger seat.
5. If the head restraint of the child seat cannot be fully extended when it is installed in the vehicle, this will result in restrictions on the maximum size setting for child restraint sys‐tems in weight category II or III.
   Contact with the roof when the head restraint is fully extended and locked in place will not result in any restrictions on use.
6. The child restraint system must not be put under strain between the roof and the seat cushion and/or be installed facing the wrong direction.
7. The child restraint system must not be put under strain by the head restraint. Adjust the head restraints as appropriate.
8. Never place objects (e.g. cushions) under or behind the child restraint system.
   The seat belt on the front passenger side is equipped with a special seat belt retractor.

When enabled, the special seat belt retractor ensures that the seat belt does not slacken once the child seat is secured.

1. Set the front passenger seat as far back as possible and move the seat into the highest position if possible.
2. Adjust the seat cushion inclination so that the front edge of the seat cushion is in the highest position and the back edge of the seat cushion is in the lowest position.
3. Set the seat backrest to the most vertical position possible.
4. Install the child restraint system.
   The entire base of the child restraint system must always rest on the sitting surface of the front passenger seat.
5. Always make sure that the shoulder belt strap is correctly routed from the seat belt outlet of the vehicle to the shoulder belt guide on the child restraint system.
   The shoulder belt strap must be routed forwards and downwards from the seat belt out‐let.
6. If necessary, adjust the front passenger seat accordingly.

Child safety locks
Activating or deactivating the child safety lock for the rear doors

WARNING
Risk of accident and injury due to children left unattended in the vehicle

If children are left unsupervised in the vehi‐cle, they could, in particular:

1. Open doors, thereby endangering other persons or road users.
2. Get out and be struck by oncoming traffic.
3. Operate vehicle equipment and become trapped, for example.

In addition, the children could also set the vehicle in motion, for example by:

1. Releasing the parking brake.
2. Changing the transmission position.
3. Starting the vehicle.
4. Never leave children unattended in the vehicle.
5. When leaving the vehicle, always take the SmartKey with you and lock the vehicle.
   Keep the vehicle SmartKey out of reach of children.

WARNING
Danger to life due to exposure to extreme heat or cold in the vehi‐cle
If people, particularly children, are exposed to extreme temperatures over an extended period of time, there is a risk of serious injury or danger to life.

If children are traveling in the vehicle, they could, in particular:

1. Open doors, thereby endangering other persons or road users.
2. Get out and be struck by oncoming traffic.
3. Operate vehicle equipment and become trapped, for example.
4. Always activate the installed child safety locks if children are traveling in the vehicle.
5. Never leave children unattended in the vehicle.
6. When leaving the vehicle, always take the SmartKey with you and lock the vehicle.

There are child safety locks for the rear doors and the rear passenger compartment side win‐dows.
The child safety lock on the rear doors secures each door separately. The doors can no longer be opened from the inside.

Press the lever in direction 1 (activate) or 2 (deactivate).
Make sure that the child safety locks are working properly.

Activating or deactivating the child safety lock for the rear side windows

To activate/deactivate: press button 2.
The rear side window can be opened or closed in the following cases:

1. Indicator lamp 1 is lit: via the switch on the driver’s door
2. Indicator lamp 1 is off: via the switch on the corresponding rear door or driver’s door                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         Notes on pets in the vehicle
   WARNING
   Risk of accident and injury due to animals left unsecured or unat‐tended in the vehicle
   If you leave animals in the vehicle unatten‐ded or unsecured, they could possibly press buttons or switches.

An animal may:

1. Activate vehicle equipment and become trapped, for example
2. Switch systems on or off and endanger other road users
   

Unsecured animals may be thrown around in the vehicle in the event of an accident or sudden steering and braking maneuvers and injure vehicle occupants in the process.

1. Never leave animals in the vehicle unattended.
2. Always correctly secure animals while driving, e.g. using a suitable animal car‐rier.

FAQs

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