MERCEDES-BENZ GLA 2019 Repair Manual
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GWARNING
If persons, particularly children are subjec-
ted 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.
Protect it with a blanket, for example. If the
child restraint system has been exposed to
direct sunlight, let it cool down before secur-
ing the child in it. Never leave children unat-
tended in the vehicle.
Child-proof locks for the rear doors
You secure each door individually with thechild-proof locks on the rear doors. A doorsecured with a child-proof lock cannot beopened from inside the vehicle. When the vehi-cle is unlocked, the door can be opened fromthe outside.
XTo activate:press the child-proof lock leverup in the direction of arrow C.
XMake sure that the child-proof locks areworking properly.
XTo deactivate:press the child-proof locklever down in the direction of arrow D.
Override feature for the rear side win-
dows
XTo activate/deactivate:press button C.If indicator lamp Dis lit, operation of therear side windows is disabled. Operation isonly possible using the switches in the driv-er's door. If indicator lamp Dis off, opera-tion is possible using the switches in therear compartment.
Pets in the vehicle
GWARNING
If you leave animals unsupervised or unse-
cured in the vehicle, they may press buttons
or switches, for instance.
In this way, animals may:
Ractivate vehicle equipment and become
trapped, for example
Rswitch systems on or off and thereby
endanger other road users
Furthermore, unsecured animals may be
flung around inside the vehicle in the event
of an accident or abrupt steering or braking
maneuver, and thereby injure vehicle occu-
pants. There is a risk of accident and injury.
Never leave animals unattended in the vehi-
cle.
Always secure animals properly when driv-
ing, for instance with a suitable pet carrier.
Pets in the vehicle59
Safety
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Driving safety systems
Overview of driving safety systems
In this section, you will find information aboutthe following driving safety systems:
RABS (Anti-lockBrakingSystem)(Ypage 60)
RBAS (BrakeAssistSystem) (Ypage 61)
RActive Brake Assist (Ypage 61)
RESP®(ElectronicStabilityProgram)(Ypage 63)
REBD (ElectronicBrake forceDistribution)(Ypage 67)
RADAPTIVE BRAKE (Ypage 67)
RSTEER CONTROL (Ypage 67)
Important safety notes
If you fail to adapt your driving style or if youare inattentive, the driving safety systems canneither reduce the risk of an accident noroverride the laws of physics. Driving safetysystems are merely aids designed to assistdriving.
You are responsible for maintaining the dis-tance to the vehicle in front, for vehicle speed,for braking in good time, and for staying inlane. Always adapt your driving style to suitthe prevailing road and weather conditions andmaintain a safe distance from the vehicle infront. Drive carefully.
The driving safety systems described onlywork as effectively as possible when there isadequate contact between the tires and theroad surface. Please pay special attention tothe notes on tires, recommended minimumtire tread depths, etc. (Ypage 305).
In wintry driving conditions, always use wintertires (M+S tires) and if necessary, snowchains. Only in this way will the driving safetysystems described in this section work aseffectively as possible.
ABS (Anti-lock Braking System)
General information
ABS regulates brake pressure in such a waythat the wheels do not lock when you brake.
This allows you to continue steering the vehi-cle when braking.
The %ABS warning lamp in the instrumentcluster lights up when the ignition is switchedon. It goes out when the engine is running.
ABS works from a speed of about 5 mph(8 km/h), regardless of road-surface condi-tions. ABS works on slippery surfaces, evenwhen you only brake gently.
Important safety notes
iObserve the "Important safety notes" sec-tion (Ypage 60).
GWARNING
If ABS is malfunctioning, the wheels could
lock when braking. The steerability and
braking characteristics would be severely
affected. There is an increased danger of
skidding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
When ABS is malfunctioning, other systems,including driving safety systems, will alsobecome inoperative. Observe the informationon the ABS warning lamp (Ypage 233) anddisplay messages which may be shown in theinstrument cluster (Ypage 204).
Braking
XIf ABS intervenes:continue to depress thebrake pedal vigorously until the braking sit-uation is over.
XTo make a full brake application:depressthe brake pedal with full force.
If ABS intervenes when braking, you will feel apulsing in the brake pedal.
The pulsating brake pedal can be an indicationof hazardous road conditions, and functions asa reminder to take extra care while driving.
Off-road ABS
An ABS system specifically suited to off-roadterrain is activated automatically once the off-road program is activated (Ypage 170).
At speeds below 20 mph (30 km/h), the frontwheels lock cyclically during braking. The dig-ging-in effect achieved in the process reduces
60Driving safety systems
Saf ety
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the stopping distance on off-road terrain. Thislimits steering capability.
BAS (Brake Assist System)
General information
BAS operates in emergency braking situations.If you depress the brake pedal quickly, BASautomatically boosts the braking force, thusshortening the stopping distance.
Important safety notes
iObserve the "Important safety notes" sec-tion (Ypage 60).
GWARNING
If BAS is malfunctioning, the braking dis-
tance in an emergency braking situation is
increased. There is a risk of an accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.
Braking
XKeep the brake pedal firmly depressed untilthe emergency braking situation is over.ABS prevents the wheels from locking.
The brakes will function as usual once yourelease the brake pedal. BAS is deactivated.
Active Brake Assist
General information
iObserve the "Important safety notes" sec-tion (Ypage 60).
Active Brake Assist consists of a distancewarning function with an autonomous brakingfunction and a situation-dependent brakeboosting effect.
Active Brake Assist can help you to minimizethe risk of a collision with the vehicle travelingin front or reduce the effects of such a colli-sion.
If Active Brake Assist detects that there is arisk of collision, you will be warned visuallyand acoustically. If you do not react to the vis-
ual collision warning or the warning tone,autonomous braking can be initiated in criticalsituations. If you apply the brake yourself in acritical situation, Active Brake Assist supportsyou with a situation-dependent brake boostingeffect.
Important safety notes
Detection of hazardous situations can be par-ticularly impaired if:
RThere is dirt on the sensors or anything elsecovering the sensors
RThere is snow or heavy rain
RThere is interference by other radar sources
RThere are strong radar reflections, for exam-ple in parking garages
RA narrow vehicle is traveling in front, e.g. amotorbike
RA vehicle is traveling in front on a differentline
RYou are driving a new vehicle or servicing onthe Active Brake Assist system has justbeen carried out
Observe the important safety notes in the"Breaking-in notes" section (Ypage 124).
Following damage to the front end of the vehi-cle, have the configuration and operation ofthe radar sensor checked at a qualified spe-cialist workshop. This also applies to collisionsat low speeds where no visible damage to thefront of the vehicle is apparent.
Activating/deactivating
Active Brake Assist is active after every igni-tion cycle.
You can activate or deactivate Active BrakeAssist (Ypage 197) in the on-board com-puter. When deactivated, the distance warningfunction and the autonomous braking functionare also deactivated.
If Active Brake Assist is deactivated, the
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Distance warning function
General information
The distance warning function can help you tominimize the risk of a front-end collision with avehicle ahead or reduce the effects of such acollision. If the distance warning functiondetects that there is a risk of a collision, youwill be warned visually and acoustically.
Important safety notes
iObserve the "Important safety notes" sec-tion for driving safety systems (Ypage 60).
GWARNING
The distance warning function does not
react:
Rto people or animals
Rto oncoming vehicles
Rto crossing traffic
Rwhen cornering
The distance warning function may not give
warnings in all critical situations. There is a
risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake.
Always adapt your speed to suit the prevail-
ing road and traffic conditions.
GWARNING
The distance warning function cannot
always clearly identify objects and complex
traffic situations.
In such cases, the distance warning function
may:
Rgive an unnecessary warning
Rnot give a warning
There is a risk of an accident.
Always pay careful attention to the traffic
situation and do not rely solely on the dis-
tance warning function.
Function
Starting at a speed of approximately 4 mph(7 km/h),the distance warning function warnsyou if you rapidly approach a vehicle in front.An intermittent warning tone will then sound,
and the
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Situation-dependent braking assis-
tance
General information
iObserve the "Important safety notes" sec-tion (Ypage 60).
With the help of the radar sensor system,Active Brake Assist can detect obstacles thatare in the path of your vehicle for an extendedperiod of time.
If Active Brake Assist detects a risk of collisionwith the vehicle in front, it calculates the brakepressure necessary to avoid a collision. If youapply the brakes forcefully, situation-depend-ent braking assistance adapts to the situationand automatically increases the brake pres-sure to a degree appropriate to the traffic sit-uation.
Situation-dependent braking assistance pro-vides braking assistance in hazardous situa-tions at speeds above 4 mph (7 km/h). It usesradar sensor technology to assess the trafficsituation.
Situation-dependent braking assistance iscapable of reacting to moving objects thathave already been detected as such at leastonce over the period of observation, up tovehicle speeds of around 155 mph(250 km/h).
Situation-dependent braking assistance canalso detect stationary objects, up to vehiclespeeds of around 44 mph (70 km/h).
XKeep the brake pedal depressed until theemergency braking situation is over.ABS prevents the wheels from locking.
The brakes will work normally again if:
Ryou release the brake pedal
Rthere is no longer any danger of a collision
Rno obstacle is detected in front of your vehi-cle
Situation-dependent braking assistance is thendeactivated.
Important safety notes
iObserve the "Important safety notes" sec-tion for driving safety systems (Ypage 60).
GWARNING
Active Brake Assist does not react:
Rto persons, bicycles, motorcycles or ani-
mals
Rto approaching vehicles
Rto cross traffic
Ron bends
As a result, Active Brake Assist cannot inter-
vene in all critical situations. There is a risk
of an accident.
Always pay careful attention to the traffic
situation and be prepared to brake.
GWARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist might:
Rintervene unnecessarily
Rnot intervene
There is a risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake. Terminate
the intervention in a non-critical driving sit-
uation.
Due to the nature of the system, complex butnon-critical driving conditions may also causeActive Brake Assist to intervene.
Even if Active Brake Assist is not available dueto a malfunction in the radar sensor system,the brake system is still available with fullbrake boosting effect and BAS.
ESP®(Electronic Stability Program)
General notes
iObserve the "Important safety notes" sec-tion (Ypage 60).
ESP®monitors driving stability and traction,i.e. power transmission between the tires andthe road surface.
If ESP®detects that the vehicle is deviatingfrom the direction desired by the driver, one ormore wheels are braked to stabilize the vehi-
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Safety
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cle. The engine output is also modified to keepthe vehicle on the desired course within physi-
cal limits. ESP®assists the driver when pulling
away on wet or slippery roads. ESP®can alsostabilize the vehicle during braking.
ETS/4ETS (Electronic Traction System)
iObserve the "Important safety notes" sec-tion (Ypage 60).
ETS traction control is part of ESP®. On vehi-
cles with 4MATIC, 4ETS is part of ESP®.
Traction control brakes the drive wheels indi-vidually if they spin. This enables you to pullaway and accelerate on slippery surfaces, forexample if the road surface is slippery on oneside. In addition, more drive torque is transfer-red to the wheel or wheels with traction.
Traction control remains active, even if you
deactivate ESP®.
Off-road 4ETS (Electronic Traction Sys-
tem)
A 4ETS system specifically suited to off-roadterrain is activated automatically once the off-road program is activated (Ypage 170).
Important safety notes
iObserve the "Important safety notes" sec-tion (Ypage 60).
GWARNING
If ESP®is malfunctioning, ESP®is unable to
stabilize the vehicle. Additionally, further
driving safety systems are deactivated. This
increases the risk of skidding and an acci-
dent.
Drive on carefully. Have ESP®checked at a
qualified specialist workshop.
Vehicles without 4MATIC:when towing yourvehicle with the front axle raised, it is impor-
tant that you observe the notes on ESP®
(Ypage 299).
If the
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Only deactivate ESP®in the situations
described in the following.
The spinning of the wheels results in a cuttingaction for better traction on loose surfaces.
It may be best to deactivate ESP®in the fol-lowing situations:
Rwhen using snow chains
Rin deep snow
Ron sand or gravel
iActivate ESP®as soon as the situations
described above no longer apply. ESP®willotherwise not be able to stabilize the vehicleif the vehicle starts to skid or a wheel startsto spin.
!Avoid spinning the driven wheels for an
extended period with ESP®deactivated. Youcould otherwise damage the drivetrain.
Deactivating/activating ESP®
You can deactivate or activate ESP®via theon-board computer (Ypage 197).
ESP®deactivated:
The