Problems with automatic front-passenger front airbag deactivation
Be sure to observe the notes on "System self-test" (Y
page 53).Problem
Possible causes/consequences and
M
MSolutions The PASSENGER AIR
BAG OFF indicator lamp
lights up and remains lit,
even though the front-
passenger seat is occu-
pied by an adult or a per-
son with a build corre-
sponding to that of an
adult. The classification of the person on the front-passenger seat is false.
X Make sure the conditions for a correct classification of the person
on the front-passenger seat are met (Y page 50).
X If the PASSENGER AIR BAG OFF indicator lamp remains lit, the front-
passenger seat may not be used.
X Have the automatic front-passenger front airbag deactivation sys-
tem checked immediately at a qualified specialist workshop. The PASSENGER AIR
BAG OFF indicator lamp
does not light up and/or
does not stay on.
The front-passenger seatis:
R empty
R occupied with a rear-
ward-facing child
restraint system The automatic front-passenger front airbag deactivation system is
malfunctioning.
X Make sure there is nothing between the seat and the child restraint
system.
X Make sure that the entire base of the child restraint system rests on
the seat cushion of the front-passenger seat.
X When installing the child restraint system, make sure that the seat
belt is tight. Do not pull the seat belt tight with the front-passenger
seat adjustment. This could result in the seat belt and the child
restraint system being pulled too tightly.
X Check that the child restraint system is installed correctly.
X Make sure that no objects are applying additional weight to the
seat.
X If the PASSENGER AIR BAG OFF indicator lamp remains off and/or
the PASSENGER AIR BAG ON indicator lamp lights up, do not install
a rearward-facing child restraint system on the front-passenger
seat. It is recommended that you fit the child restraint system to a suitable rear seat.
X Have the automatic front-passenger front airbag deactivation sys-
tem checked immediately at a qualified specialist workshop. Deployment of belt tensioners and air-
bags
Important safety notes G
WARNING
After the airbag deploys, the airbag parts are
hot. There is a risk of injury.
Do not touch the airbag parts. Have a
deployed airbag replaced at a qualified spe-
cialist workshop as soon as possible. G
WARNING
Pyrotechnical belt tensioners which have
been triggered are no longer operational and
therefore cannot protect as intended. There is an increased risk of injury, possibly even fatal.
Have pyrotechnic belt tensioners which have
been triggered replaced at a qualified special-
ist workshop immediately.
Mercedes-Benz recommends that you have the
vehicle towed to a qualified specialist workshop
after an accident. Take this into account, par-
ticularly if a seat belt tensioner was triggered or
an airbag was deployed. 54
Occupant safetySafety
An electric motor is used by PRE-SAFE
®
to trig-
ger the tightening of the seat belt in hazardous
situations. This procedure is reversible.
If the belt tensioners are triggered or an airbag is
deployed, you will hear a bang, and a small
amount of powder may also be released. The
6 restraint system warning lamp lights up.
Only in rare cases will the bang affect your hear-
ing. In general, the powder released is not haz-
ardous to health but may cause short-term
breathing difficulties to persons suffering from
asthma or other pulmonary conditions. Provided it is safe to do so, you should leave the vehicle
immediately or open the window in order to pre-
vent breathing difficulties.
Operation During the first stage of a collision, the restraint
system control unit evaluates important physi-
cal data relating to vehicle deceleration or accel-
eration, such as:
R duration
R direction
R intensity
Based on the evaluation of this data, the
restraint system control unit triggers the seat
belt tensioners in the event of a head-on or rear
collision.
A seat belt tensioner can be triggered only if:
R the ignition is switched on
R the components of the restraint system are
operational. You can find further information
under: "Restraint system warning lamp"
(Y page 43)
R the belt tongue has engaged in the belt buckle
of the respective front seat
The seat belt tensioners in the rear compart-
ment are triggered independently of the lock
status of the seat belts.
If the restraint system control unit detects a
high-severity accident, in certain head-on colli-
sions, additional components of the restraint
system are deployed independently of each
other:
R front airbags and driver's kneebag
R windowbag, if the system determines that
deployment can offer additional protection to
that provided by the seat belt
On vehicles with the automatic front-passenger
front airbag deactivation system: depending on the person in the front-passenger seat, the front-passenger front airbag is either disabled or
enabled. The front-passenger front airbag can
be deployed in an accident only if the
PASSENGER AIR BAG OFF indicator lamp is off.
Observe the information on the PASSENGER AIR BAG indicator lamps (Y page 43).
Your vehicle has two-stage front airbags. In the
first deployment stage, the front airbag is filled
with propellant gas to reduce the risk of injuries. The front airbag is fully deployed if the second
deployment stage is activated within a few mil-
liseconds.
The activation threshold for the seat belt ten-
sioners and airbags is determined based on the
evaluation of the vehicle's rate of deceleration
or acceleration at various points in the vehicle.
This process is pre-emptive in nature. The trig-
gering/deployment process should take place
in good time at the start of the collision.
The rate of vehicle deceleration or acceleration
and the direction of the force are essentially
determined by:
R the distribution of forces during the collision
R the collision angle
R the deformation characteristics of the vehicle
R the characteristics of the object with which
the vehicle has collided
Factors that can be seen and measured only
after a collision has occurred do not play a deci-
sive role in the deployment of an airbag, nor do
they provide an indication of airbag deployment.
The vehicle may be deformed significantly with-out an airbag being deployed. This is the case if
only parts that are relatively easily deformed are
affected and the rate of deceleration is not high. Conversely, an airbag may be deployed even
though the vehicle suffers only minor deforma-
tion. This is the case if, for example, very rigid
vehicle parts such as longitudinal body mem-
bers are hit, and sufficient deceleration occurs
as a result.
If the restraint system control unit detects a side
impact or if the vehicle overturns, the applicable components of the restraint system are activa-
ted independently of each other depending on
the apparent type of accident.
R Sidebags on the side on which an impact
occurs, independently of the seat belt ten-
sioner and seat belt usage
Vehicles with the automatic front-passenger
front airbag deactivation system: the sidebag Occupant safety
55Safety Z
Override feature for the rear side win-
dows X
To activate/deactivate: press button:.
If indicator lamp ;is lit, operation of the rear
side windows is disabled. Operation is only
possible using the switches in the driver's
door. If indicator lamp ;is off, operation is
possible using the switches in the rear com-
partment. Pets in the vehicle
G
WARNING
If you leave animals unsupervised or unse-
cured in the vehicle, they may push a button
or a switch, for example.
They could:
R activate vehicle equipment and become
trapped, for example
R switch vehicle systems on or off, thus
endangering other road users
In the event of an accident, sudden braking or
abrupt changes of direction, unsecured ani-
mals could be flung around the vehicle, injur-
ing the vehicle occupants. There is a risk of an accident and injury.
Never leave animals unattended in the vehi-
cle. Always secure animals correctly during a
journey, e.g. in an animal transport box. Driving safety systems
Driving safety systems overview
In this section, you will find information about
the following driving safety systems:
R ABS (A nti-lock Braking System)
(Y page 69)
R BAS (Brake AssistSystem) (Y page 69)
R Active Brake Assist (Y page 70)
R Adaptive brake lights (Y page 72)
R ESP ®
(Electronic StabilityProgram)
(Y page 73)
R EBD (e lectronic brake force distribution)
(Y page 75)
R ADAPTIVE BRAKE (Y page 75)
R Active Brake Assist with cross-traffic function
(Y page 75)
R STEER CONTROL (Y page 78) Important safety notes
If you fail to adapt your driving style or if you are
inattentive, the driving safety systems can nei-
ther reduce the risk of an accident nor override the laws of physics. Driving safety systems are
merely aids designed to assist driving. You are
responsible for maintaining the distance to the
vehicle in front, for vehicle speed, for braking in
good time, and for staying in lane. Always adapt your driving style to suit the prevailing road and
weather conditions and maintain a safe distance from the vehicle in front. Drive carefully.
The driving safety systems described only work
as effectively as possible when there is ade-
quate contact between the tyres and the road
surface. Pay particular attention to the informa- tion regarding tyres, recommended minimum
tyre tread depths etc. in the "Wheels and tyres" section (Y page 361).
In wintry driving conditions, always use winter
tyres (M+S tyres) and, if necessary, snow
chains. Only in this way will the driving safety
systems described in this section work as effec-
tively as possible. 68
Driving safety systemsSafety
ABS (Anti-lock Braking System)
General notes ABS regulates brake pressure in such a way that
the wheels do not lock when you brake. This
allows you to continue steering the vehicle when braking.
The ! ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
ABS works from a speed of about 8 km/h,
regardless of road-surface conditions. ABS
works on slippery surfaces, even when you only
brake gently.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 68). G
WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid- ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
If ABS is malfunctioning, other systems, includ-
ing driving safety systems, will also become
inoperative. Observe the information on the ABS warning lamp (Y page 293) and display mes-
sages which may be shown in the instrument
cluster (Y page 259).
Braking X
If ABS intervenes: continue to depress the
brake pedal with force until the braking sit-
uation is over.
X To make a full brake application: depress
the brake pedal with full force.
If ABS intervenes when braking, you will feel a
pulsing in the brake pedal.
The pulsating brake pedal can be an indication
of hazardous road conditions; this serves as a
reminder to take extra care while driving. Off-road ABS An ABS system specifically suited to off-road
terrain is activated automatically once an off-
road program is activated:
R Vehicles without the Off-Road Engineering
package (Y page 228)
R Vehicles with the Off-Road Engineering pack-
age (Y page 229)
At speeds below 30 km/h the front wheels lock cyclically during braking. The digging-in effect
achieved in the process reduces the stopping
distance when driving off-road. This limits steer- ing capability. BAS (Brake Assist System)
General notes BAS operates in emergency braking situations.
If you depress the brake pedal quickly, BAS
automatically boosts the braking force, thus
shortening the stopping distance.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 68). G
WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.
Braking X
Keep the brake pedal depressed firmly until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. Driving safety systems
69Safety Z
Function
The distance warning function issues a warning
at speeds:
R of approximately 30 km/h or more, if, over
several seconds, the distance maintained to
the vehicle travelling in front is insufficient.
The · distance warning lamp then lights
up in the instrument cluster.
R of approximately 7 km/h or more, if you rap-
idly approach a vehicle in front. An intermit-
tent warning tone will then sound and the
· distance warning lamp will light up in the
instrument cluster.
X Brake immediately to increase the distance
from the vehicle in front.
or
X Take evasive action provided it is safe to do
so.
Due to the nature of the system, certain com-
plex but non-critical driving conditions may also
cause the system to display a warning.
With the help of the radar sensor system, the
distance warning function can detect obstacles
that are in the path of your vehicle for an exten-
ded period of time.
Up to a speed of approximately 70 km/h, the
distance warning function can also react to sta- tionary obstacles, such as stopped or parked
vehicles.
Autonomous braking function If the driver does not react to the distance warn-
ing signal in a critical situation, Active Brake
Assist can assist the driver with the autonomous
braking function.
The autonomous braking function is available in
the following speed ranges:
R 7 - 105 km/h for moving objects
R 7 - 50 km/h for stationary objects
Due to the nature of the system, complex but
non-critical driving conditions may also cause
the autonomous braking function to engage.
If the autonomous braking function demands
particularly high braking force, preventative
passenger protection measures (PRE-SAFE ®
)
are activated simultaneously (Y page 56).Adaptive Brake Assist General information
i Observe the "Important safety notes" sec-
tion (Y page 68).
With the help of the radar sensor system, Adap-
tive Brake Assist can detect obstacles that are in the path of your vehicle for an extended period
of time.
If Adaptive Brake Assist detects a risk of colli-
sion with the vehicle in front, it calculates the
brake pressure necessary to avoid a collision. If
you apply the brakes forcefully, Adaptive Brake
Assist automatically increases the brake pres-
sure to a level suitable for the traffic conditions.
Adaptive Brake Assist provides braking assis-
tance in hazardous situations at speeds above
7 km/h. It uses the radar sensor system to
assess the traffic situation.
Up to a speed of approximately 250 km/h,
Adaptive Brake Assist is capable of reacting to
moving objects that have already been detected
as such at least once over the period of obser-
vation.
Up to a speed of approximately 70 km/h, Adap-
tive Brake Assist reacts to stationary obstacles.
If Adaptive Brake Assist demands a particularly
high braking force, preventative passenger pro- tection measures (PRE-SAFE ®
) are activated
simultaneously (Y page 56).
X Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally again if: R you release the brake pedal
R the risk of collision with the vehicle in front
has passed
R no obstacle is detected in the path of your
vehicle
Adaptive Brake Assist is then deactivated.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 68). G
WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions. Driving safety systems
71Safety
Z
In such cases, Adaptive Brake Assist can:
R intervene unnecessarily
R not intervene
There is a risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake. Terminate the
intervention in a non-critical driving situation. G
WARNING
Adaptive Brake Assist does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
As a result, the Adaptive Brake Assist may not intervene in all critical conditions. There is a
risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake.
Due to the nature of the system, particularly
complicated but non-critical driving conditions
may also cause Brake Assist to intervene.
If Adaptive Brake Assist is not available due to a malfunctioning radar sensor system, the brake
system remains available with full brake boost-
ing effect and BAS. Adaptive brake lights
The adaptive brake lights warn following traffic
in an emergency braking situation by:
R flashing brake lamps
R switching on the hazard warning lamps
If you brake sharply from a speed of more than
50 km/h or are assisted by the Brake Assist, the
brake lamps flash rapidly. In this way, traffic
travelling behind you is warned in an even more
noticeable manner.
If you brake sharply from a speed of more than
70 km/h to a standstill, the hazard warning
lamps are activated automatically. If the brakes are applied again, the brake lamps light up con-
tinuously. The hazard warning lamps switch off
automatically if you travel faster than 10 km/h. You can also switch off the hazard warning lamps using the hazard warning button
(Y
page 122). ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes" sec-
tion (Y page 68).
ESP ®
monitors driving stability and traction, i.e.
power transmission between the tyres and the
road surface.
If ESP ®
detects that the vehicle is deviating from
the direction desired by the driver, one or more
wheels are braked to stabilise the vehicle. The
engine output is also modified to keep the vehi- cle on the desired course within physical limits.
ESP ®
assists the driver when pulling away on
wet or slippery roads. ESP ®
can also stabilise
the vehicle during braking.
4ETS (Electronic Traction System) 4ETS traction control is part of ESP
®
.
Traction control brakes the drive wheels indi-
vidually if they spin. This enables you to pull
away and accelerate on slippery surfaces, for
example if the road surface is slippery on one
side. In addition, more drive torque is transfer-
red to the wheel or wheels with traction.
Traction control remains active if you deactivate
ESP ®
.
In appropriate driving situations, activate the
off-road programs:
X Vehicles without the Off-Road Engineering
package (Y page 228)
X Vehicles with the Off-Road Engineering pack-
age (Y page 229)
Off-road 4ETS (Electronic Traction Sys-
tem) An ETS system specifically suited to off-road
terrain is activated automatically once an off-
road program is activated:
R Vehicles without the Off-Road Engineering
package (Y page 228)
R Vehicles with the Off-Road Engineering pack-
age (Y page 229) 72
Driving safety systemsSafety
Important safety notes
G
WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilise the vehicle. In addition, other driving
safety systems are switched off. This increa-
ses the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.
! Only operate the vehicle for a maximum of
ten seconds on a brake dynamometer. Switch off the ignition.
Application of the brakes by ESP ®
may oth-
erwise destroy the brake system.
! A function or performance test should only
be carried out on a twin-axle dynamometer.
Before you operate the vehicle on such a
dynamometer, please consult a qualified
workshop. You could otherwise damage the
drive train or the brake system.
When ESP ®
is deactivated, the åESP®
OFF
warning lamp lights up continuously.
If the ÷ warning lamp and the åwarning
lamp are lit continuously, ESP ®
is not available
due to a malfunction.
Observe the information on warning lamps
(Y page 295) and display messages which may
be shown in the instrument cluster
(Y page 259).
i Only use wheels with the recommended tyre
sizes. Only then will ESP ®
function properly.
Characteristics of ESP ®General notes
If the ÷ ESP warning lamp goes out before
beginning the journey, ESP ®
is automatically
active.
If ESP ®
intervenes, the ÷ESP®
warning lamp
flashes in the instrument cluster.
If ESP ®
intervenes:
X Do not deactivate ESP ®
under any circum-
stances.
X When pulling away, only depress the acceler-
ator pedal as far as is necessary.
X Adapt your driving style to suit the prevailing
road and weather conditions. ECO start/stop function
The ECO start/stop function switches the
engine off automatically if the vehicle stops
moving. When pulling away again, the engine
starts automatically. ESP ®
remains in its previ-
ously selected status, e.g. if ESP ®
was deacti-
vated before the engine was automatically
switched off.
Deactivating/activating ESP ® Important safety notes
i Observe the "Important safety notes" sec-
tion (Y page 68).
You can select between the following ESP ®
sta-
tuses:
R ESP ®
is activated
R ESP ®
is deactivated G
WARNING
If you deactivate ESP ®
, ESP ®
no longer sta-
bilises the vehicle. There is an increased risk
of skidding and an accident.
Only deactivate ESP ®
in the situations descri-
bed in the following.
In the following situations, it may be better to
deactivate ESP ®
:
R when snow chains are used
R in deep snow
R on sand or gravel
Spinning the wheels results in a cutting action,
which enhances traction.
i Activate ESP ®
as soon as the situations
described above no longer apply. ESP ®
will
otherwise not stabilise the vehicle if the vehi-
cle starts to skid or a wheel starts to spin. Driving safety systems
73Safety Z
Deactivating/activating ESP
®X
To deactivate: press button:.
The å ESP®
OFF warning lamp on the
instrument cluster lights up.
X To activate: press button :.
The å ESP®
OFF warning lamp on the
instrument cluster goes out.
Characteristics when ESP ®
is deactivated
If ESP ®
is deactivated and one or more wheels
start to spin, the ÷ESP®
warning lamp in the
instrument cluster flashes. In such situations,
ESP ®
will not stabilise the vehicle.
If you deactivate ESP ®
:
R ESP ®
no longer improves driving stability
R engine torque is no longer limited and the
drive wheels may start to spin
R traction control is still activated
R Active Brake Assist is no longer available; it is
not activated even if you brake firmly with
assistance from ESP ®
R PRE-SAFE ®
is not available; it is not activated
even if you brake firmly with assistance from
ESP ®
R Active Brake Assist with cross-traffic function
is no longer available; it is not activated even
if you brake firmly with assistance from ESP ®
R ESP ®
continues to provide assistance when
the brakes are firmly applied Off-road ESP
®
(vehicles with Off-Road
Engineering package) An ESP
®
system specifically suited to off-road
terrain is activated automatically once an off-
road program is activated.
R Vehicles without the Off-Road Engineering
package (Y page 228)
R Vehicles with the Off-Road Engineering pack-
age (Y page 229)
Off-road ESP ®
intervenes with a delay if there is
oversteering or understeering, thus improving
traction.
ESP ®
trailer stabilisation General notes
ESP ®
trailer stabilisation is not available in
Mercedes-AMG vehicles.
If your vehicle/trailer combination begins to
lurch, ESP ®
assists you in this situation. ESP ®
slows the vehicle down by braking and limiting
the engine output until the vehicle/trailer com- bination has stabilised.
Important safety notes G
WARNING
If road and weather conditions are poor,
trailer stabilisation will not be able to prevent the vehicle/trailer combination from swerv-
ing. Trailers with a high centre of gravity can
tip over before ESP ®
can detect this. There is
a risk of an accident.
Always adapt your driving style to the prevail-
ing road and weather conditions.
If your vehicle/trailer combination begins to
lurch, you can only stabilise the vehicle/trailer
combination by depressing the brake firmly.
Trailer stabilisation is active above speeds of
about 60 km/h.
ESP ®
trailer stabilisation does not work if ESP ®
is deactivated or disabled because of a malfunc- tion. 74
Driving safety syste
msSafety