2014 MERCEDES-BENZ S-Class ECU

Otherwise, the vehicle's electronic
system may be damaged.
R the transmission is locked in position P
after disconnecting the battery. The
vehicle is secured against rolling away.
You can then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be installed securely
during operation.
Comply with safety precautions and take
protective measures when handling
batteries. Risk of explosion.
Fire, open flames and smoking are
prohibited when handling the
battery. Avoid creating sparks. Battery acid is caustic. Avoid
contact with skin, eyes or clothing.
Wear suitable protective clothing,
especially gloves, apron and
faceguard.
Rinse any acid spills immediately
with clear water. Contact a
physician if necessary. Wear eye protection.
Keep children away.
Observe this Operator's Manual.
For safety reasons, Mercedes–Benz
recommends that you only use batteries that
have been tested and approved for your
vehicle by Mercedes-Benz. These batteries
have greater impact resistance and as a result
there is no risk of acid burns to occupants
when a battery is damaged in an accident. In order for the battery to achieve the
maximum possible service life, it must always
be sufficiently charged.
The vehicle battery, like other batteries, can
discharge over time if you do not use the
vehicle. In this case, have the battery
disconnected at a qualified specialist
workshop. You can also charge the battery
with a charger recommended by Mercedes-
Benz. Contact a qualified specialist workshop
for further information.
Have the battery condition of charge checked
more frequently if you use the vehicle mainly
for short trips or if you leave it standing idle
for a lengthy period. Consult a qualified
specialist workshop if you wish to leave your
vehicle parked for a long period of time.
i
Remove the SmartKey if you park the
vehicle and do not require any electrical
consumers. The vehicle will then use very
little energy, thus conserving battery
power. Charging the battery
G
WARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a
risk of an explosion.
Particularly avoid fire, open flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery. G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing.
Do not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash battery acid immediately with
water and seek medical attention. G
WARNING
A discharged battery can freeze at
temperatures below freezing point. When Battery (vehicle)
371Breakdown assistance
Z

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:
R The 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.
R You may only jump-start the vehicle when the engine and exhaust system are cold.
R Do not start the engine if the battery is frozen. Let the battery thaw first.
R Only jump-start from batteries with a 12 V voltage rating.
R Only use jumper cables which have a sufficient cross-section and insulated terminal clamps.
R If the battery is fully discharged, leave the battery that is being used to jump-start connected
for a few minutes before attempting to start. This charges the battery slightly.
R Make sure that the two vehicles do not touch.
Make sure that:
R the jumper cables are not damaged.
R when the jumper cables are connected to the battery, uninsulated sections of the terminal
clamp do not come into contact with other metal sections.
R the 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.
X Secure the vehicle by applying the electric parking brake.
X Shift the transmission to position P.
X Make sure that the ignition is switched off (Y page 171). All indicator lamps in the instrument
cluster must be off. When using the SmartKey, turn the SmartKey to position 0in the ignition
lock and remove it (Y page 171).
X Switch off all electrical consumers, e.g. rear window defroster, lighting, etc.
X Open the hood. Example: earth point cover
X
Turn fasteners 0043one 00C4turn and remove.
X Remove the cover whilst pressing down on trim panel 0044of the washer fluid reservoir. 374
Jump-startingBreakdown assistance

Towing and tow-starting
Important safety notes
G
WARNING
Functions relevant to safety are restricted or
no longer available if:
R the engine is not running.
R the brake system or the power steering is
malfunctioning.
R there is a malfunction in the voltage supply
or the vehicle's electrical system.
If your vehicle is being towed, much more
force may be necessary to steer or brake.
There is a risk of an accident.
In such cases, use a tow bar. Before towing,
make sure that the steering moves freely. G
WARNING
You can no longer steer the vehicle if the
steering wheel lock has been engaged. There
is a risk of an accident.
Always switch off the ignition when towing the
vehicle with a tow cable or a tow bar. G
WARNING
If the weight of the vehicle to be towed or tow-
started is greater than the permissible gross
weight of your vehicle:
R the towing eye could detach itself
R the vehicle/trailer combination could
rollover.
There is a risk of an accident.
When towing or tow-starting another vehicle,
its weight should not be greater than the
permissible gross weight of your vehicle.
! If DISTRONIC PLUS or the HOLD function
is activated, the vehicle brakes
automatically in certain situations. To
prevent damage to the vehicle, deactivate
DISTRONIC PLUS and the HOLD function in
the following or other similar situations:
R when towing the vehicle
R in the car wash !
Make sure that the electric parking brake
is released. If the electric parking brake is
faulty, visit a qualified specialist workshop.
! Secure the tow rope or tow bar to the
towing eye only. Otherwise, the vehicle
could become damaged.
! Do not use the towing eye for recovery,
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.
! Shift the automatic transmission to Nand
do not open the driver's or front
passenger's door during towing. The
automatic transmission may otherwise
shift to position P, which could damage the
transmission.
! Do not tow with sling-type equipment.
This could damage the vehicle.
! The vehicle can be towed a maximum of
30 miles (50km). The towing speed of
30 mph (50 km/h) must not be exceeded.
If the vehicle has to be towed more than
30 miles (50km), the entire vehicle must be
raised and transported.
! If you tow or tow-start another vehicle, its
weight must not exceed the maximum
permissible gross vehicle weight of your
vehicle.
Information on your vehicle's gross vehicle
weight rating can be found on the vehicle
identification plate (Y page 422).
It is better to have the vehicle transported
than to have it towed.
If the vehicle has suffered transmission
damage, have it transported on a transporter
or trailer.
The automatic transmission must be in
position Nwhen the vehicle is being towed.
If the automatic transmission cannot be
shifted to position N, have the vehicle
transported on a transporter or trailer. 376
Towing and tow-startingBreakdown assistance

In order to ensure that the automatic
transmission stays in position Nwhen towing
the vehicle, you must observe the following
points:
X You must use the SmartKey instead of the
Start/Stop button (Y page 171).
X Make sure that the vehicle is stationary and
the SmartKey in the ignition lock is in
position 0.
X Turn the SmartKey to position 2in the
ignition lock.
X Depress and hold the brake pedal.
X Shift the automatic transmission to
position N.
X Release the brake pedal.
X Release the electric parking brake.
X Leave the SmartKey in position 2in the
ignition lock.
X Switch on the hazard warning lamps
(Y page 140).
i In order to signal a change of direction
when towing the vehicle with the hazard
warning lamps switched on, use the
combination switch as usual. In this case,
only the indicator lamps for the direction of
travel flash. After resetting the
combination switch, the hazard warning
lamp starts flashing again. Transporting the vehicle
! 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.
The towing eyes or trailer tow hitch can be
used to pull the vehicle onto a trailer or
transporter if you wish to transport it.
X Turn the SmartKey to position 2in the
ignition lock.
X Shift the automatic transmission to
position N. As soon as the vehicle has been loaded:
X
Prevent the vehicle from rolling away by
applying the electric parking brake.
X Shift the automatic transmission to
position P.
X Turn the SmartKey to position 0in the
ignition lock and remove it.
X Secure the vehicle. 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 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
(Y page 373).
Have the vehicle transported on a transporter
or trailer. Tow-starting (emergency engine
starting)
! Vehicles with automatic transmission
must not be tow-started. You could
otherwise damage the automatic
transmission.
i Information on "Jump-starting"
(Y page 373). 378
Towing and tow-startingBreakdown assistance

Fuses
Important safety notes
G
WARNING
If you manipulate or bridge a faulty fuse or if
you replace it with a fuse with a higher
amperage, 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.
The fuse allocation chart is on the fuse box in
the trunk (Y page 380).
If a newly inserted fuse also blows, have the
cause traced and rectified at a qualified
specialist 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. Otherwise, components or
systems could be damaged.
The fuses in your vehicle serve to close down
faulty circuits. If a fuse blows, all the
components on the circuit and their functions
stop operating. Before changing a fuse
X Secure the vehicle against rolling away
(Y page 190).
X Switch off all electrical consumers.
X Make sure that the ignition is switched off
(Y page 171).
or
X When using the SmartKey, turn the
SmartKey to position 0in the ignition lock
and remove it (Y page 171). All indicator lamps in the instrument cluster
must be off.
The fuses are located in various fuse boxes:
R
Fuse box on the driver's side of the
dashboard
R Fuse box in the front-passenger footwell
R Fuse box in the engine compartment on the
left-hand side of the vehicle, when viewed
in the direction of travel
R Fuse box in the trunk on the right-hand side
of the vehicle, when viewed in the direction
of travel Dashboard fuse box
! Do not use a pointed object such as a
screwdriver to open the cover in the
dashboard. You could damage the
dashboard or the cover.
! 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.
X Open the driver's door. X
To open: pull cover 0043outwards in the
direction of the arrow and remove it.
X To close: clip in cover 0043on the front of
the dashboard.
X Fold cover 0043inwards until it engages. Fuses
379Breakdown assistance Z

Fuse box in the front-passenger
footwell
! 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.
X Open the front-passenger door. X
Fold cover 0043down and remove it. Fuse box in the engine compartment
G
WARNING
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.
X Open the hood. X
To open: release retaining clamps 0043and
remove cover 0044. X
Use a dry cloth to remove any moisture
from the fuse box.
X Undo screws 0087on the fuse box.
X Remove fuse box cover 0085forwards.
X To close: check whether the seal is lying
correctly in cover 0085.
X Insert cover 0085at the rear of the fuse box
into the retainer.
X Fold down cover 0085of the fuse box and
tighten screws 0087.
X Insert cover 0044and secure with retaining
clamps 0043.
X Close the hood. Fuse box in the trunk
! 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 380
FusesBreakdown assistance

Underinflated or overinflated tires
Underinflated tires G
WARNING
Tires with pressure that is too low can
overheat and burst as a consequence. In
addition, they also suffer from excessive and/
or irregular wear, which can severely impair
the braking properties and the driving
characteristics. There is a risk of an accident.
Avoid tire pressures that are too low in all the
tires, including the spare wheel.
Underinflated tires may:
R overheat, leading to tire defects
R adversely affect handling
R wear excessively and/or unevenly
R have an adverse effect on fuel consumption
Overinflated tires G
WARNING
Tires with excessively high pressure can burst
because they are damaged more easily by
road debris, potholes etc. In addition, they
also suffer from irregular wear, which can
severely impair the braking properties and the
driving characteristics. There is a risk of an
accident.
Avoid tire pressures that are too high in all the
tires, including the spare wheel.
Overinflated tires may:
R increase the braking distance
R adversely affect handling
R wear excessively and/or unevenly
R have an adverse effect on ride comfort
R be more susceptible to damage Maximum tire pressures 0043
Example: maximum permissible tire
pressure
Never exceed the maximum permissible tire
inflation pressure. Always observe the
recommended tire pressure for your vehicle
when adjusting the tire pressure
(Y page 387).
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration. Checking the tire pressures
Important safety notes Observe the notes on tire pressure
(Y
page 387).
Information on air pressure for the tires on
your vehicle can be found:
R on the vehicle's Tire and Loading
Information placard on the B-pillar
R on the tire pressure label on the fuel filler
flap
R in the "Tire pressure" section
Checking tire pressures manually To determine and set the correct tire
pressure, proceed as follows:
X
Remove the valve cap of the tire that is to
be checked.
X Press the tire pressure gauge securely onto
the valve. 390
Tire pressureWheels and tires

Curb weight
The weight of a vehicle with standard
equipment including the maximum capacity
of fuel, oil and coolant. It also includes the air-
conditioning system and optional equipment
if these are installed in the vehicle, but does
not include passengers or luggage.
Maximum load rating
The maximum load rating is the maximum
permissible 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:
R if the vehicle has been parked without
direct sunlight on the tires for at least three
hours and
R if 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 sits
securely on the 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 5 lbs (2.3 kg). 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
accessories.
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
distributed over the tire tread. If the tire tread
is level with the bars, the wear limit of 00CDin
(1.6 mm) has been reached. 406
All about wheels and tiresWheels and tires