2016 MERCEDES-BENZ C CLASS key battery

Problems with fuel and the fuel tank Problem
Possible causes/consequences and P Solutions
Fuel is leaking from the
vehicle.
G WARNING
The fuel line or the fuel tank is faulty.
Risk of explosion or fire. X
Apply the electric parking brake. X
Switch off the engine. X
Remove the SmartKey from the ignition lock.
or, in vehicles with KEYLESS-GO start-function or KEYLESS ‑ GOX
Open the driver's door.
The on-board electronics now have status 0 . This is the same as the
SmartKey having been removed. X
Do not restart the engine under any circumstances. X
Consult a qualified specialist workshop.
The fuel filler flap cannot
be opened. The fuel filler flap is not unlocked. X
Unlock the vehicle ( Y
page 81).X
PLUG-IN HYBRID Vehicles: depressurize the fuel tank
( Y
page 165).
The SmartKey battery is discharged or nearly discharged. X
Unlock the vehicle using the mechanical key ( Y
page 83).
The fuel filler flap is unlocked, but the opening mechanism is jammed. X
Consult a qualified specialist workshop.
Charging the high-voltage battery
(PLUG-IN HYBRID vehicles)
Important safety notes
G DANGER
The vehicle's high-voltage electrical system is
under high voltage. If you modify components
in the vehicle's high-voltage electrical system
or touch damaged components, you may be
electrocuted. The components in the vehi-
cle's high-voltage electrical system may be
damaged in an accident, although the damage
is not visible. There is a risk of fatal injury.
Following an accident, do not touch any high-
voltage components and never modify the
vehicle's high-voltage electrical system. Have
the vehicle towed away after an accident and the vehicle's high-voltage electrical system
checked by a qualified specialist workshop.
G WARNING
In the event of a vehicle fire, the internal pres-
sure of the high-voltage battery can exceed a
critical value. In this case flammable gas
escapes through a ventilation valve on the
underbody. The gas can ignite. There is a risk
of injury.
Leave the danger zone immediately. Secure
the danger area at a suitable distance, whilst
observing legal requirements.
G DANGER
If you use incorrectly installed mains sockets
or adapters, extension cables or similar to
connect the charging cable to a mains socket,168
Charging the high-voltage battery (PLUG-IN HYBRID vehicles)
Driving and parking

Problems with the charging process Problem
Possible causes/consequences and P Solutions
The charge socket flap
cannot be opened. The charge socket flap is not unlocked. X
Unlock the vehicle ( Y
page 81).
If the key battery is discharged: X
Unlock the driver's door using the mechanical key ( Y
page 83).
or X
Unlock the vehicle centrally from the inside ( Y
page 88).
The charge socket flap is unlocked, but the opening mechanism is
jammed. X
Lock the vehicle and unlock it again.
If, after that, the opening mechanism is still jammed: X
Consult a qualified specialist workshop.
The high-voltage battery
is not being charged. The indicator lamp on the vehicle socket does not light up or flashes
red.
A malfunction has occurred during the initialization of the charging
process or during charging. X
Disconnect the charging cable connector from the vehicle socket
and plug it back into the vehicle socket.
If the problem persists: X
Use a different charging station.
or X
Consult a qualified specialist workshop.
The high-voltage battery
is not charged during the
charging process when
connected to a power
socket. The electrical outlet is faulty. X
Have the electrical outlet checked to test if it is functioning prop-
erly.
or X
Use a different electrical outlet.
The charging cable con-
nector cannot be
removed from the vehi-
cle socket. The snap fastener on the charging cable connector is locked. X
Press and hold the button on the charging cable connector. The
snap fastener on the vehicle socket is unlocked. X
Remove the charging cable connector from the vehicle socket.
If the snap fastener on the charging cable connector is locked: X
Press and hold the button on the charging cable connector and try
to release the lock.Charging the high-voltage battery (PLUG-IN HYBRID vehicles) 175
Driving and parking Z

Hybrid drive system Display messages
Possible causes/consequences and P Solutions
r Vehicle Operational
Switch the Ignition
Off Before Exiting PLUG-IN HYBRID vehicles:
You are exiting the vehicle when it is in a ready-to-drive state. The
READY indicator in the multifunction display is on. A warning tone also
sounds.
If you leave the vehicle: X
Secure the vehicle against rolling away ( Y
page 177).X
Switch off the ignition and remove the SmartKey.
If you do not leave the vehicle: X
Switch off the electrical consumers, e.g. automatic climate control,
seat heating.
Please note the following: The electrical consumers are supplied by
the 12 V battery. If the vehicle is left in a ready-to-drive state for an
extended period, it will switch off once the 12 V battery is almost
empty. It will then only be possible to start the vehicle using a second
battery (jump-starting).
Change the current
drive program
before changing the
operating mode. or
Exit manual drive
program M before
changing the operat‐
ing mode. PLUG-IN HYBRID vehicles:
You have attempted to change the operating mode in the automatic
drive program S (Sport), S+ (Sport Plus) or in the manual drive pro-
gram M . X
Activate drive program C (Comfort) or E (Economy) ( Y
page 229).X
Select the preferred operating mode HYBRID , E-MODE , E-SAVE or
CHARGE ( Y
page 226).
E-MODE Currently
Unavailable PLUG-IN HYBRID vehicles:
The condition of charge of the high-voltage battery has dropped to the
lower limit and the E-MODE operating mode has been switched off.
Driving with the internal combustion engine is activated and the oper-
ating mode switches to the basic HYBRID setting.X
Continue driving using the internal combustion engine.
You can switch to the E-SAVE or CHARGE operating mode as
required ( Y
page 226).
If you select CHARGE , the high-voltage battery is charged.
Once the charge level display for the high-voltage battery has
increased slightly, you can switch to the E-MODE operating mode
again.272
Display messages
On-board computer and displays

when the engine is switched off or at very
low speeds. Otherwise, when in transmis-
sion position D or R the automatic trans-
mission will automatically switch to park
position P and block the wheels.R
Operating with the Start/Stop button:
Do not open the driver's door when the
engine is switched off or at very low
speeds. Otherwise, when in transmission
position D or R the automatic transmission
will automatically switch to park position P
and block the wheels.
Observe the following to make sure that the
automatic transmission stays in position N neu-
tral:
Operating with the SmartKey and Start/Stop
button: X
Make sure that the ignition is switched on. X
Make sure that the vehicle is stationary. X
Depress and hold the brake pedal.
Operating with the Start/Stop button only: X
Engage park position P .X
Release the brake pedal. X
Remove Start/Stop button from ignition lock
( Y
page 146).X
Insert the SmartKey into the ignition lock. X
Switch on the ignition. X
Depress and hold the brake pedal.
Operating with the SmartKey and Start/Stop
button: X
Shift to neutral N .X
Release the brake pedal. X
Release the electric parking brake, if neces-
sary. X
Switch off the ignition and leave the SmartKey
in the ignition lock.
You can wash the vehicle in an automatic car
wash from the very start.
If the vehicle is very dirty, pre- wash it bef ore
c leaning it in an automatic car wash.
After using an automatic car wash, wipe off wax
from the windshield and the wiper blades. This
will prevent smears and reduce wiping noises
caused by residue on the windshield. Washing by hand In some countries, washing by hand is only
allowed at specially equipped washing bays.
Observe the legal requirements in each country. X
Do not use hot water and do not wash the
vehicle in direct sunlight. X
Use a soft sponge to clean. X
Use a mild cleaning agent, such as a car
shampoo approved by Mercedes-Benz. X
Thoroughly hose down the vehicle with a gen-
tle jet of water. X
Do not point the water jet directly towards the
air inlet. X
Use plenty of water and rinse out the sponge
frequently. X
Rinse the vehicle with clean water and dry
thoroughly with a chamois. X
Do not let the cleaning agent dry on the paint-
work.
Carefully remove all deposits of road salt as
soon as possible when driving in winter.
Power washers
G WARNING
The water jet from a circular jet nozzle (dirt
blasters) can cause invisible exterior damage
to the tires or chassis components. Compo-
nents damaged in this way may fail unexpect-
edly. There is a risk of an accident.
Do not use power washers with circular jet
nozzles to clean the vehicle. Have damaged
tires or chassis components replaced imme-
diately.
! Always maintain a distance of at least
11.8 in (30 cm) between the vehicle and the
power washer nozzle. Information about the
correct distance is available from the equip-
ment manufacturer.
Move the power washer nozzle around when
cleaning your vehicle.
Do not aim directly at any of the following: R
tires R
door gaps, roof gaps, joints, etc. R
electrical components R
battery R
connectors336
Care
Maintenance and care

Observe the service intervals in the Mainte-
nance Booklet or contact a qualified specialist
workshop for more information.
! Always have work on batteries carried out at
a qualified specialist workshop. Should it, in
exceptional circumstances, be absolutely
necessary to disconnect the 12-volt battery
yourself, observe the following: R
secure the vehicle to prevent it from rolling
away. R
switch off the ignition. R
always disconnect the negative terminal
clamp first, followed by the positive termi-
nal clamp.
After the battery has been disconnected, the
transmission is locked in position P .
After the work has been done, install the bat-
tery and replace the cover of the positive ter-
minal clamp firmly.
Comply with safety precautions and take pro-
tective measures when handling batteries.
Risk of explosion.
Fire, open flames and smoking are
prohibited when handling the bat-
tery. Avoid creating sparks.
Electrolyte or battery acid is corro-
sive. Avoid contact with skin, eyes or
clothing.
Wear suitable protective clothing,
especially gloves, apron and face-
guard.
Immediately rinse electrolyte or acid
splashes off with clean water. Con-
tact a physician if necessary.
Wear eye protection.
Keep children away.
Observe this Operator's Manual.
For safety reasons, Mercedes-Benz recom-
mends that you only use batteries which have been tested and approved for your vehicle by
Mercedes-Benz. These batteries provide
increased impact protection to prevent vehicle
occupants from suffering acid burns should the
battery be damaged in the event of an accident.
In order for the battery to achieve the maximum
possible service life, it must always be suffi-
ciently charged.
The vehicle battery, like other batteries, can dis-
charge 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 special-
ist 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.
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.
PLUG-IN HYBRID vehicles: if the battery
charge is sufficient, the high-voltage battery can
also supply the 12 V battery. This only happens
if the condition of charge of the 12 V battery
requires this, e.g. after using electrical consum-
ers for an extended period with the engine
switched off. As the on-board voltage is contin-
uously monitored this can also be performed
when the engine is switched off. The condition of
charge of the 12 V battery and the on-board
voltage are thereby kept stable for a longer
period.
High-voltage battery – important
safety notes Only PLUG-IN HYBRID vehicles are equipped
with a high-voltage battery.
G DANGER
The vehicle's high-voltage electrical system is
under high voltage. If you modify components
in the vehicle's high-voltage electrical system
or touch damaged components, you may be
electrocuted. The components in the vehi-
cle's high-voltage electrical system may beBattery (vehicle) 349
Breakdown 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
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 a s 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. All indicator lamps in the instrument cluster must be
off. When using the SmartKey, turn the SmartKey to position 0 in the ignition lock and remove it
( Y
page 146). X
Switch off all electrical consumers, e.g. rear window defroster, lighting, etc. X
Open the hood.
Position number

! When towing, pull away slowly and
smoothly. If the tractive power is too high, the
vehicles could be damaged.
! Shift the automatic transmission to N and
do not open the driver's or front passenger's
door during towing. The automatic transmis-
sion 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.
It is better to have the vehicle transported than
to have it towed away.
If the vehicle has suffered transmission damage,
have it transported on a transporter or trailer.
The automatic transmission must be in position
N when the vehicle is being towed. If the auto-
matic transmission cannot be shifted to position
N , have the vehicle transported on a transporter
or trailer.
The battery must be connected and charged.
Otherwise, you: R
cannot turn the SmartKey to position 2 in the
ignition lock R
cannot release the electric parking brake R
cannot shift the automatic transmission to
position N
Disarm the automatic locking feature before the
vehicle is towed ( Y
page 89). You could other-
wise be locked out when pushing or towing the
vehicle.
PLUG-IN HYBRID vehicles:
PLUG-IN HYBRID vehicles may not be towed
away but must instead be transported, if: R
the multifunction display is not working or R
the á Towing Not Permitted See
Operator's Manual message appears in the
multifunction display
If the vehicle is in a dangerous area, it can be
towed out of that area with both axles on the
ground. In this case, the towing distance must
not be greater than 165 ft (50 m) and must not
exceed a towing speed of 6 mph (10 km/ h) . For longer distances, have the vehicle loaded and
transported.
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 C .X
Remove the towing eye from the vehicle tool
kit ( Y
page 343). X
Press the mark on cover C inwards and
remove. X
Screw in the towing eye clockwise as far as it
will go and tighten it.
Removing the towing eye X
Unscrew and remove the towing eye. X
Attach cover C to the bumper and press until
it engages. X
Put the towing eye back into the vehicle tool
kit.
Towing the vehicle with the rear axle
raised
Only vehicles without 4MATIC can be towed
with the rear axle raised.
PLUG-IN HYBRID vehicles: towing the vehicle
away with the rear axle raised should only be
carried out by professional recovery companies.Towing and tow-starting 355
Breakdown assistance Z

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 sys-
tem: 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 352).
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 dam-
age the automatic transmission.
i You can find information on "Jump-starting"
under ( Y
page 352).
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 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.
The fuse allocation chart is on the fuse box in the
trunk ( Y
page 357).
If a newly inserted fuse also blows, have the
cause traced and rectified at a qualified special-
ist 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.
! 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 seep-
ing in or dirt could otherwise impair the oper-
ation of the fuses.
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 Observe the important safety notes
( Y
page 357) X
Secure the vehicle against rolling away
( Y
page 177). X
Switch off the engine. X
Switch off all electrical consumers. X
Remove the SmartKey from the ignition lock.
or, in vehicles with KEYLESS-GO start-function
or KEYLESS ‑ GO X
Open the driver's door.
The on-board electronics now have status 0 .
This is the same as the SmartKey having been
removed.
The driver’s door can be closed again.
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
driver's side R
Fuse box under the trunk floor 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 screw-
driver to open the cover in the dashboard. You
could damage the dashboard or the cover. Fuses 357
Breakdown assistance Z