ECU MERCEDES-BENZ GLA-Class 2017 X156 Manual PDF

Always make sure that neither you nor the
battery is electrostatically charged. A build-
up of electrostatic charge can be caused, for
example:
Rby wearing clothing made from synthetic
fibers
Rdue to friction between clothing and seats
Rif you push or pull the battery across the
carpet or other synthetic materials
Rif you wipe the battery with a cloth
GWARNING
During the charging process, a battery produ-
ces hydrogen gas. If a short circuit occurs or
sparks are created, the hydrogen gas can
ignite. There is a risk of an explosion.
RMake sure that the positive terminal of a
connected battery does not come into con- tact with vehicle parts.
RNever place metal objects or tools on a bat-
tery.
RIt is important that you observe the descri-
bed order of the battery terminals when
connecting and disconnecting a battery.
RWhen jump-starting, make sure that the
battery poles with identical polarity are
connected.
RIt is particularly important to observe the
described order when connecting and dis-
connecting the jumper cables.
RNever connect or disconnect the battery
terminals while the engine is running.
GWARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with skin, eyes or clothing. Do
not inhale any battery gases. Do not lean over
the battery. Keep children away from batter-
ies. Wash away battery acid immediately with
plenty of clean water and seek medical atten-
tion.
HEnvironmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separately and recycled to protect the
environment.
Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified spe-
cialist workshop or a special
collection point for used bat-
teries.
!Have the battery checked regularly at a
qualified specialist workshop.
Observe the service intervals in the Main-
tenance Booklet or contact a qualified spe-
cialist workshop for more information.
!You should have all work involving the
battery carried out at a qualified specialist
workshop. In the exceptional case that it is
necessary for you to disconnect the battery
yourself, make sure that:
Ryou switch off the engine and remove the
key. On vehicles with KEYLESS-GO,
ensure that the ignition is switched off.
Check that all the indicator lamps in the
instrument cluster are off. Otherwise,
electronic components, such as the
alternator, may be damaged.
Ryou first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps.
Otherwise, the vehicle's electronic sys-
tem may be damaged.
Rin vehicles with automatic transmission,
the transmission is locked in position P
after disconnecting the battery. The vehi-
cle is secured against rolling away. Yo u
ca

n then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be installed securely
during operation.
328Battery (vehicle)
Breakdo wn assis tance

Do not start the vehicle using a rapid charging device. If your vehicle's battery is discharged,
the engine can be jump-started from another vehicle or from a second battery using jumper
cables. Observe the following points:
RThe battery is not accessible in all vehicles. If the other vehicle's battery is not accessible,
jump-start the vehicle using a second battery or a jump-starting device.
RYou may only jump-start the vehicle when the engine and exhaust system are cold.
RDo not start the engine if the battery is frozen. Let the battery thaw first.
ROnly jump-start from batteries with a 12 V voltage rating.
ROnly use jumper cables that are not damaged and have a sufficient cross-section and insu-
lated terminal clamps.
RMake sure that the two vehicles do not touch.
Make sure that:
Rthe jumper cables are not damaged.
Rnon-insulated parts of the terminal clamps do not come into contact with other metal parts
while the jumper cables are connected to the battery.
RThe jumper cables cannot come into contact with parts which can move when the engine is
running, such as the V-belt pulley or the fan.
XSecure the vehicle by applying the electric parking brake.
XShift the transmission to position P.
XTurn the SmartKey to position 0in the ignition lock and remove it.
XSwitch off all electrical consumers, e.g. rear window defroster, lighting, etc.
XOpen the hood.
Position number Bidentifies the charged battery of the other vehicle or an equivalent jump-
starting device.
XPress together cover :of positive clamp ;and slide it back.
XConnect positive terminal ;on your vehicle to positive terminal =of donor battery B
using the jumper cable, beginning with your own battery.
332Jump-starting
Breakdown assistance

!Make sure that the electric parking brake
is released. If the electric parking brake is
faulty, visit a qualified specialist workshop.
!Only secure the tow rope or tow bar at the
towing eyes. Otherwise, the vehicle could
be damaged.
!Do not use the towing eyes for recovery
purposes as this could damage the vehicle. If in doubt, recover the vehicle with a crane.
!When towing, pull away slowly and
smoothly. If the tractive power is too high,
the vehicles could be damaged.
!The vehicle can be towed a maximum of
30 miles (50km). The towing speed of
30 mph (50km/h) must not be exceeded.
If the vehicle has to be towed more than
30 miles (50km), the front axle must be
raised or the entire vehicle raised and
transported.
!Do not tow with sling-type equipment.
This could damage the vehicle.
!When towing vehicles with KEYLESS-GO,
use the key instead of the Start/Stop but-
ton. Otherwise, the automatic transmission
may shift to position Pwhen the driver's or
front-passenger door are opened, which
could lead to damage to the transmission.
!Vehicles with automatic transmission
must not be started by tow-starting. This
could otherwise damage the transmission.
It is better to have the vehicle transported
than to have it towed away.
If the vehicle can no longer be driven because of an accident or breakdown, you have the
following options:
RTransporting the vehicle
As a rule, you should have the vehicle trans-
ported.
RTowing the vehicle with a tow rope or tow
bar
Only tow the vehicle in exceptional cases. The battery must be connected and charged.
Otherwise, you:
Rcannot turn the SmartKey to position 2in
the ignition lock
Rcannot release the electric parking brake
Rcannot shift the transmission to position N
The function of the electric parking brake and the parking lock is dependent on the on-board
voltage.
If the on-board voltage is low or there is a
system malfunction, it is possible that:
Rthe electric parking brake may not be
applied in certain circumstances, or
Rthe transmission may not be shifted to P
Switch off non-essential consumers, e.g. the
radio.
Disarm the automatic locking feature before
the vehicle is towed (
Ypage 230). You could
otherwise be locked out when pushing or
towing the vehicle.
Installing/removing the towing eye
Installing the towing eye
The brackets for the screw-in towing eye are
located in the bumpers. They are at the rear
and at the front, under covers :.
334Towing and tow-starting
Breakdown assistance

XDepress and hold the brake pedal.
XShift the automatic transmission to posi-
tionN.
XLeave the SmartKey in position 2in the
ignition lock.
XRelease the brake pedal.
XRelease the electric parking brake.
XSwitch on the hazard warning lamps
(
Ypage 119).
iIn order to signal a change of direction
when towing the vehicle with the hazard
warning lamps switched on, use the com-
bination switch as usual. In this case, only
the indicator lamps for the direction of
travel flash. After resetting the combina-
tion switch, the hazard warning lamp starts
flashing again.
Transporting the vehicle
4MATIC vehicles/vehicles with auto-
matic transmission
!When the vehicle is loaded for transport,
the front and rear axles must be stationary
and on the same transportation vehicle.
Positioning over the connection point of the
transport vehicle is not permitted. The drive
train may otherwise be damaged.
All vehicles
!You may only secure the vehicle by the
wheels, not by parts of the vehicle such as axle or steering components. Otherwise,
the vehicle could be damaged.
XTurn the SmartKey to position
2in the igni-
tion lock (
Ypage 149).
XShift the transmission to position N.
As soon as the vehicle has been loaded:
XPrevent the vehicle from rolling away by
applying the electric parking brake.
XShift the transmission to position P.
XTurn the SmartKey to position 0in the igni-
tion lock and remove it.
XSecure the vehicle.
The towing eye can be used to pull the vehicle
onto a trailer or transporter for transporting
purposes.
Notes on 4MATIC vehicles
!
Vehicles with 4MATIC must not be towed
with either the front or the rear axle raised,
as doing so will damage the transmission.
Vehicles with 4MATIC may only either be
towed away with both axles on the ground or
be loaded up and transported.
If the vehicle's transmission, front, or rear
axle is damaged, have the vehicle transported
on a truck or trailer.
In the event of damage to the electrical
system:
If the battery is defective, the automatic
transmission will be locked in position P. To
shift the automatic transmission to position
N, you must provide power to the vehicle's
electrical system in the same way as when
jump-starting (
Ypage 331).
Have the vehicle transported on a transporter
or trailer.
336Towing and tow-starting
Breakdown assistance

Tow-starting (emergency engine
starting)
!
Vehicles with automatic transmission
must not be tow-started. You could other-
wise damage the automatic transmission.
iYou can find information on "Jump-start-
ing" under (
Ypage 331).
Fuses
Important safety notes
GWARNING
If you manipulate or bridge a faulty fuse or if
you replace it with a fuse with a higher amper- age, the electric cables could be overloaded.
This could result in a fire. There is a risk of an
accident and injury.
Always replace faulty fuses with the specified
new fuses having the correct amperage.
Blown fuses must be replaced with fuses of
the same rating, which you can recognize by
the color and value. The fuse ratings are listed
in the fuse allocation chart.
If a newly inserted fuse also blows, have the
cause traced and rectified at a qualified spe-
cialist workshop, e.g. an authorized
Mercedes-Benz Center.
!Only use fuses that have been approved
for Mercedes-Benz vehicles and which
have the correct fuse rating for the system
concerned. Only use fuses marked with an
"S". Otherwise, components or systems
could be damaged.
The fuses in your vehicle serve to close down
faulty circuits. If a fuse blows, all the compo-
nents on the circuit and their functions stop
operating.
Before changing a fuse
XSecure the vehicle against rolling away
(
Ypage 171).
XSwitch off all electrical consumers.
XVehicles without KEYLESS-GO: remove
the SmartKey from the ignition lock.
XVehicles with KEYLESS-GO start-func-
tion or KEYLESS-GO: open the driver's
door.
The on-board electronics now have status
0 . This is the same as the SmartKey having
been removed.
The fuses are located in various fuse boxes:
RFuse box in the engine compartment on the left-hand side of the vehicle, when viewed
in the direction of travel
RFuse box in the front-passenger footwell
The fuse allocation chart is on the fuse box in
the front-passenger footwell (
Ypage 338).
Fuse box in the engine compartment
GWARNING
When the hood is open and the windshield
wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windshield wipers and
the ignition before opening the hood.
!Make sure that no moisture can enter the
fuse box when the cover is open.
!When closing the cover, make sure that it
is lying correctly on the fuse box. Moisture
seeping in or dirt could otherwise impair
the operation of the fuses.
Fuses337
Breakdown assistance
Z

Checking tire pressures manually
To determine and set the correct tire pres-
sure, proceed as follows:
XRemove the valve cap of the tire that is to
be checked.
XPress the tire pressure gauge securely onto
the valve.
XRead the tire pressure and compare it to
the recommended value on the Tire and
Loading Information placard or the tire
pressure table (
Ypage 343).
XIf the tire pressure is too low, increase the
tire pressure to the recommended value.
XIf the tire pressure is too high, release air.
To do so, press down the metal pin in the
valve, using the tip of a pen for example.
Then check the tire pressure again using
the tire pressure checker.
XScrew the valve cap onto the valve.
XRepeat these steps for the other tires.
Tire pressure loss warning system
(Canada only)
General notes
While the vehicle is in motion, the tire pres-
sure loss warning system monitors the set
tire pressure using the rotational speed of the
wheels. This enables the system to detect
significant pressure loss in a tire. If the speed
of rotation of a wheel changes as a result of a
loss of pressure, a corresponding warning
message will appear in the multifunction dis-
play.
You can recognize the tire pressure loss warn-
ing by the Run Flat Indicator Active
Press 'OK' to Restartmessage in the
multifunction display in the Serv.
menu.
Information on the message display can be
found in the "Restarting the tire pressure loss
warning system" section (
Ypage 347).
Important safety notes
The tire pressure warning system does not
warn you of an incorrectly set tire pressure.
Observe the notes on the recommended tire
pressure (
Ypage 343).
The tire pressure loss warning does not
replace the need to regularly check the tire
pressure. An even loss of pressure on several tires at the same time cannot be detected by
the tire pressure loss warning system.
The tire pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the
tire is penetrated by a foreign object. In the
event of a sudden loss of pressure, bring the
vehicle to a halt by braking carefully. Avoid
abrupt steering movements.
The function of the tire pressure loss warning
system is limited or delayed if:
Rsnow chains are mounted on your vehicle's
tires.
Rroad conditions are wintry.
Ryou are driving on sand or gravel.
Ryou adopt a very sporty driving style (cor-
nering at high speeds or driving with high
rates of acceleration).
Ryou are driving with a heavy load (in the
vehicle or on the roof).
Restarting the tire pressure loss warn-
ing system
Restart the tire pressure loss warning system
if you have:
Rchanged the tire pressure
Rchanged the wheels or tires
Rmounted new wheels or tires
XBefore restarting, make sure that the tire
pressures are set properly on all four tires
for the respective operating conditions.
The recommended tire pressure can be
found on the Tire and Loading Information
placard on the B-pillar. Additionally, a tire
pressure table is attached to the fuel filler
flap. The tire pressure loss warning system can only give reliable warnings if you have
Tire pressure347
Wheels and tires
Z

DOT (Department of Transportation)
DOT-markedtires fulfill th erequirements of
th e U S Departmen tof Transportation .
Normal occupant weigh t
The number of occupant sfo rwhic hth evehi-
cle is designed multiplie dby 68 kilograms
(15 0lbs) .
Unifor mTire Qualit yGrading Standards
A uniform standard to grade th equalit yof
tires wit hregards to tread quality, tire traction
and temperature characteristics .The qualit y
gradin gassessmen tis made by th emanufac -
turer following specification sfrom th eU.S.
government. The ratings are molded into th e
sidewall of th etire.
Recommended tire pressure s
The recommended tire pressur eapplies to
th etires mounted at th efactory.
The Tir eand Loadin gInformation placard con-
tains th erecommended tire pressures fo r
cold tires on afull yloade dvehicl eand fo rth e
maximum permissibl evehicl espeed.
The tire pressur etable contain sth erecom-
mended pressures fo rcold tires fo rvarious
operating conditions, i.e. differin gload and
speed conditions.
Increased vehicle weigh tdu eto optiona l
equipment
The combine dweight of all standard and
optional equipmen tavailable fo rth evehicle,
regardless of whether it is a
ctually installed
on th evehicl eor not.
Ri m
This is th epart of th ewhee lon whic hth etire
is mounted.
GAW R(Gross Axle Weight Rating)
The GAW Ris th emaximum gross axl eweight
rating. The actual load on an axl emus tnever
exceed th egross axl eweight rating. The
gross axl eweight ratin gcan be found on th e
vehicl eidentification plat eon th eB-pillar on
th edriver's side . Speed rating
The speed ratin
gis part of th etire identifica-
tion .It specifies th espeed range fo rwhic hth e
tire is approved.
GV W(Gross Vehicle Weight )
The gross vehicl eweight includes th eweight
of th evehicl eincludin gfuel ,tools ,th espar e
wheel, accessories installed ,occupants, lug-
gage and th edrawbar noseweight ,if applica-
ble. The gross vehicl eweight mus tno texceed
th egross vehicl eweight ratin gGVWR as
specified on th evehicl eidentification plat eon
th eB-pillar on th edriver's side .
GVWR (Gross Vehicle Weight Rating)
The GVWR is th emaximum permissibl egross
weight of afull yloade dvehicl e(the weight of
th evehicl eincludin gall accessories, occu-
pants ,fuel, luggage and th edrawbar nose-
weight ,if applicable). The gross vehicl e
weight ratin gis specified on th
eve
hicl eiden -
tification plat eon th eB-pillar on th edriver's
side .
Maximum loaded vehicle weigh t
The maximum weight is th esum of :
Rthecur bweight of th evehicl e
Rtheweight of th eaccessories
Rth eload limi t
Rtheweight of th efactory installed optional
equipmen t
Kilopascal (kPa)
Metric uni tfo rtire pressure. 6. 9kP acorre-
spond sto 1psi .Another uni tfo rtire pressur e
is bar. 10 0kilopascal s(kPa) are th eequiva-
len tof 1bar.
Load index
In addition to th eload-bearin gindex ,th eload
index may also be imprinte don th esidewall of
th etire. This specifies th eload-bearin gcapa-
cit ymor eprecisely.
All about wheels and tires36 1
Wheels and tires
Z

Curb weight
The weight of a vehicle with standard equip-
ment including the maximum capacity of fuel,
oil and coolant. It also includes the air-condi-
tioning system and optional equipment if
these are installed in the vehicle, but does not
include passengers or luggage.
Maximum load rating
The maximum tire load is the maximum per-
missible weight in kilograms or lbs for which a
tire is approved.
Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire.
Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the maximum axle load of one axle
by two.
PSI (pounds per square inch)
A standard unit of measure for tire pressure.
Aspect ratio
Relationship between tire height and tire
width in percent.
Tire pressure
This is pressure inside the tire applying an
outward force to each square inch of the tire's
surface. The tire pressure is specified in
pounds per square inch (psi), in kilopascal
(kPa) or in bar. The tire pressure should only
be corrected when the tires are cold.
Cold tire pressure
The tires are cold:
Rif the vehicle has been parked with the tires
out of direct sunlight for at least three
hours and
Rif the vehicle has not been driven further
than 1 mile (1.6 km) Tread
The part of the tire that comes into contact
with the road.
Bead
The tire bead ensures that the tire sit
s
securely on t

he wheel. There are several steel
wires in the bead to prevent the tire from
coming loose from the wheel rim.
Sidewall
The part of the tire between the tread and the bead.
Weight of optional extras
The combined weight of those optional extras
that weigh more than the replaced standard
parts and more than 2.3 kg (5 lbs). These
optional extras, such as high-performance
brakes, level control, a roof rack or a high-
performance battery, are not included in the
curb weight and the weight of the accesso-
ries.
TIN (Tire Identification Number)
This is a unique identifier which can be used
by a tire manufacturer to identify tires, for
example for a product recall, and thus identify
the purchasers. The TIN is made up of the
manufacturer's identity code, tire size, tire
type code and the manufacturing date.
Load bearing index
The load bearing index (also load index) is a
code that contains the maximum load bearing
capacity of a tire.
Traction
Traction is the result of friction between the
tires and the road surface.
Treadwear indicators
Narrow bars (tread wear bars) that are dis-
tributed over the tire tread. If the tire tread is
level with the bars, the wear limit of áin
(1.6 mm) has been reached.
362All about wheels and tires
Wheels and tires

XVehicles without KEYLESS-GO:remove
the SmartKey from the ignition lock.
XVehicles with KEYLESS-GO start-func-
tion or KEYLESS-GO: open the driver's
door.
The on-board electronics now have status
0 . This is the same as the SmartKey having
been removed.
XVehicles with KEYLESS-GO start-func-
tion or KEYLESS-GO: remove the Start/
Stop button from the ignition lock
(
Ypage 149).
XMake sure that the engine cannot be star-
ted via your smartphone (
Ypage 171).
XIf included in the vehicle equipment,
remove the tire-change tool kit from the
vehicle.
XSafeguard the vehicle against rolling away
(
Ypage 171).
Securing the vehicle to prevent it from
rolling away
If your vehicle is equipped with a wheel chock,
it can be found in the tire-change tool kit
(
Ypage 322).
The folding wheel chock is an additional
safety measure to prevent the vehicle from
rolling away, for example when changing a
wheel.
XFold both plates upwards :.
XFold out lower plate;.
XGuide the lugs on the lower plate fully into
the openings in base plate =.
XPlace chocks or other suitable items under
the front and rear of the wheel that is diag-
onally opposite the wheel you wish to
change.
Raising the vehicle
GWARNING
If you do not position the jack correctly at the
appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jacking point of the vehicle.
!The jack is designed exclusively for jack-
ing up the vehicle at the jacking points.
Otherwise, your vehicle could be damaged.
Observe the following when raising the
vehicle:
RTo raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If used incor-
rectly, the jack could tip over with the vehi- cle raised.
RThe jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It must not be used for
performing maintenance work under the
vehicle.
RAvoid changing the wheel on uphill and
downhill slopes.
364Changing a wheel
Wheels and tires

RBefore raising the vehicle, secure it from
rolling away by applying the parking brake
and inserting wheel chocks. Do not disen-
gage the parking brake while the vehicle is
raised.
RThe jack must be placed on a firm, flat andnon-slip surface. On a loose surface, a
large, flat, load-bearing underlay must be
used. On a slippery surface, a non-slip
underlay must be used, e.g. rubber mats.
RDo not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able to achieve its load-
bearing capacity due to the restricted
height.
RMake sure that the distance between the
underside of the tires and the ground does
not exceed 1.2 in (3 cm).
RNever place your hands and feet under the
raised vehicle.
RDo not lie under the vehicle.
RDo not start the engine when the vehicle is
raised.
RNever open or close a door or the tailgate
when the vehicle is raised.
RMake sure that no persons are present in
the vehicle when the vehicle is raised.
XUsing lug wrench :, loosen the bolts on
the wheel you wish to change by about one
full turn. Do not unscrew the bolts com-
pletely.
Jacking points
The jacking points are located just behind the front wheel housings and just in front of the
rear wheel housings (arrows).
XTake ratchet wrench ?out of the vehicle
tool kit and place it on the hexagon nut of
jack =so that the letters AUFare visible.
XPosition jack =at jacking point ;.
XMake sure the foot of the jack is directly
beneath the jacking point.
Changing a wheel365
Wheels and tires
Z