2016 MERCEDES-BENZ C CLASS check engine

Hybrid vehicles
General notes Hybrid technology combines a fuel efficient
internal combustion engine with a powerful
electric motor.
Important safety notes
Danger of electric shock
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.
When towing a vehicle after an accident, be sure
to observe the following sections: R
Transporting the vehicle ( Y
page 356)R
Towing the vehicle with the rear axle raised
( Y
page 355)R
Towing a vehicle with both axles on the
ground ( Y
page 356)
Read the safety instructions on towing and tow-
starting ( Y
page 354). All components of the hybrid drive system are
marked with yellow warning stickers that warn
you of the danger of high voltage. The cables of
the vehicle's high-voltage electrical system are
orange in color.
The ignition must be switched off when carrying
out general tasks, such as changing bulbs or
checking the coolant level.
Automatic switching off of the hybrid
drive system If components of the restraint system are acti-
vated during an accident, the hybrid drive sys-
tem is automatically deactivated.
The hybrid drive system is not activated when
the vehicle is started if: R
an electrical short circuit is detected in the
hybrid drive system R
an electrical connection in the hybrid drive
system is disconnected
This ensures that you do not come into contact
with high voltage.
Manual switching off of the hybrid drive
system The hybrid drive system can be deactivated
manually using the high voltage switch-off
device.
! To prevent damage to the hybrid drive sys-
tem please observe the following instruc-
tions: R
only deactivate the hybrid drive system
manually in the following situations. R
work on the hybrid drive system may only
be carried out at a qualified specialist work-
shop, even when it has been deactivated
manually.
Deactivate the hybrid system manually if: R
the u restraint system warning lamp in the
instrument cluster lights up after an accident R
the vehicle is badly damaged, e.g. after an
accident, and the restraint system compo-
nents were not activated R
the vehicle is badly damaged and has to be
towed or transported44
Hybrid vehicles
Safety

X
If possible, move the vehicle out of the
danger zone: shift the transmission into posi-
tion N .X
Release the electric parking brake. X
Roll the vehicle to a safe place and park it
safely.
Get assistance from others if necessary.
The vehicle is locked automatically when the
ignition is switched on and the wheels are turn-
ing. There is therefore a risk of being locked out
if the vehicle is being pushed or tested on a
dynamometer. X
Switch the ignition off. X
Shift the transmission to position P .
Depress the electric parking brake
( Y
page 178).
Secure the vehicle against rolling away
( Y
page 380). X
To use the high-voltage switch-off device:
open the hood.
X
Press release clip C in the direction of the
arrow and pull it out. X
Pull the high voltage switch-off device D
apart until it engages in the stop position.
If the hybrid drive system has been deactivated
due to reasons mentioned above, have it
checked at a qualified specialist workshop
before reactivation.
High-voltage battery
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 WARNING
If the housing of the high-voltage battery has
been damaged, electrolyte and gases may
leak out. These are poisonous and caustic.
There is a risk of injury.
Avoid contact with skin, eyes or clothing.
Immediately rinse electrolyte splashes off
with water and seek medical attention
straight away.
PLUG-IN HYBRID vehicles: charging the high-
voltage battery ( Y
page 168).
Engine compartment Before opening the hood: X
Apply the electric parking brake. X
Shift the transmission to position P .X
Switch the ignition off. X
Remove the SmartKey from the ignition lock.
or, in vehicles with KEYLESS-GO start-function
or KEYLESS ‑ GO X
Remove the Start/Stop button from the igni-
tion lock. X
Observe the warning notes on the risk of elec-
tric shock ( Y
page 44). X
Observe the warning notices about the hood
( Y
page 330).
RBS driving safety system (Recupera-
tive Brake System) The Recuperative Brake System supports you
when braking with an electronically-controlled
brake boost mode and enables the recovery of
kinetic energy (recuperation).
Further information about the Recuperative
Brake System ( Y
page 225).Hybrid vehicles 45
Safety Z

regular intervals while the engine is running.
Therefore, malfunctions can be detected in
good time.
The u restraint system warning lamp in the
instrument cluster lights up when the ignition is
switched on. It goes out no later than a few sec-
onds after the vehicle is started. The compo-
nents of the restraint system are in operational
readiness.
A malfunction has occurred if the u restraint
system warning lamp: R
does not light up after the ignition is switched
on R
does not go out after a few seconds with the
engine running R
lights up again while the engine is running
All vehicles, except hybrid vehicles:
G WARNING
If restraint system is malfunctioning, restraint
system components may be triggered unin-
tentionally or might not be triggered at all in
the event of an accident with a high rate of
vehicle deceleration. This can affect the Emer-
gency Tensioning Device or air bag, for exam-
ple. This poses an increased risk of injury or
even fatal injury.
Have the restraint system checked and
repaired in a qualified specialist workshop as
soon as possible.
Hybrid vehicles:
G DANGER
If the restraint system is malfunctioning, indi-
vidual restraint system components may be
triggered unintentionally or might not be trig-
gered at all in the event of an accident with a
high rate of vehicle deceleration. This could
affect Emergency Tensioning Devices or air
bags, for example. The vehicle's high-voltage
electrical system may also not be deactivated
as intended in the event of an accident. You
could suffer an electric shock if you touch the
damaged components of the vehicle's high-
voltage electrical system. This poses an
increased risk of injury or even fatal injury.
Have the restraint system checked and
repaired immediately at a qualified specialist workshop. Immediately switch off the ignition
and remove the SmartKey from the ignition
lock after an accident.
PASSENGER AIR BAG indicator lamp
PASSENGER AIR BAG ON indicator lamp C and
PASSENGER AIR BAG OFF indicator lamp D are
part of the Occupant Classification System
(OCS).
The indicator lamps display the status of the
front-passenger front air bag. R
PASSENGER AIR BAG ON lights up: the front-
passenger front air bag is enabled. If, in the
event of an accident, all deployment criteria
are met, the front-passenger front air bag is
deployed. R
PASSENGER AIR BAG OFF lights up: the front-
passenger front air bag is deactivated. It will
then not be deployed in the event of an acci-
dent.
Depending on the person in the front-passenger
seat, the front-passenger front air bag must
either be deactivated or enabled; see the fol-
lowing points. You must make sure of this both
before and during a journey. R
Children in a child restraint system:
whether the front-passenger front air bag is
enabled or deactivated depends on the instal-
led child restraint system, and the age and
size of the child. Therefore, be sure to observe
the notes on the "Occupant Classification
System (OCS)" ( Y
page 54) and on "Chil-
dren in the vehicle" ( Y
page 62). There you
will also find instructions on rearward and
forward-facing child restraint systems on the
front-passenger seat. R
All other persons: depending on the classi-
fication of the person in the front-passengerOccupant safety 47
Safety Z

Important safety notes If you fail to adapt your driving style or if you are
inattentive, th e driving safet y systems can nei-
ther reduce th e ris k of an acciden t no r override
th e laws of physics . Drivin g safet y systems are
merely aids designed to assist driving . You are
responsible for maintainin g th e distanc e to th e
vehicl e in front, for vehicl e speed, for braking in
goo d time, and for staying in lane. Always adapt
your driving style to suit th e prevailing road and
weather condition s and maintai n a saf e distanc e
from th e vehicl e in front. Drive carefully.
The driving safet y systems describe d only wor k
as effectivel y as possible when there is ade-
quat e contact between th e tires and th e road
surface. Pay particular attention to th e informa-
tion regarding tires , recommended minimum
tire tread depths etc. in th e "Wheels and tires "
section ( Y
page 360).
In wintr y driving conditions, always use winte r
tires (M+ S tires )a nd if necessary, snow chains.
Only in this way will the driving safety systems
described in this section work as effectively as
possible.
ABS (Anti-lock Braking System)
General information 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 5 mph
(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.
When ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp ( Y
page 289) and dis-
play messages which may be shown in the
instrument cluster ( Y
page 256).
Braking X
If ABS intervenes: continue to depress the
brake pedal vigorously 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, and functions as a
reminder to take extra care while driving.
BAS (Brake Assist System)
General information 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 an accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.68
Driving safety systems
Safety

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
malfunction in the radar sensor system, the
brake system remains available with full brake
boosting effect and BAS.
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 tires 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 stabilize 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 stabilize
the vehicle during braking.
ETS/4ETS (Electronic Traction System)
i Observe the "Important safety notes" sec-
tion ( Y
page 68).
ETS traction control is part of ESP ®
. On vehicles
with 4MATIC, 4ETS 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, even if you
deactivate ESP ®
.
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 68).
G WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilize the vehicle. Additionally, further driv-
ing safety systems are deactivated. This
increases the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.
When towing the vehicle with the rear axle
raised, observe the notes on ESP ®
( Y
page 355).
If the

R
PRE-SAFE ®
is no longer available, nor is it
activated if you brake firmly and ESP ®
inter-
venes. R
PRE-SAFE ®
Brake is no longer available, it is
also not activated if you brake firmly and ESP ®
intervenes. R
ESP ®
still provides support when you brake
firmly.
ESP ®
trailer stabilizationGeneral information ESP ®
trailer stabilization is not available in
Mercedes-AMG vehicles.
If your vehicle/trailer combination begins to
swerve, 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 stabilized.
Important safety notes
G WARNING
If road and weather conditions are poor,
trailer stabilization will not be able to prevent
the vehicle/trailer combination from swerv-
ing. Trailers with a high center 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 with trailer (vehicle/trailer com-
bination) begins to lurch, you can only stabilize
the vehicle/trailer combination by depressing
the brake firmly.
ESP ®
trailer stabilization is active above speeds
of about 65 km/h.
ESP ®
trailer stabilization does not work if ESP ®
is deactivated or disabled because of a malfunc-
tion.
Crosswind Assist
General information
Strong crosswinds can cause your vehicle to
deviate from a straight course. The crosswind
driving assistance function integrated in ESP ®
noticeably reduces these impairments. ESP ®
intervenes automatically according to the
direction and intensity of the crosswinds affect-
ing your vehicle.
ESP intervenes with stabilizing braking to assist
you in keeping the vehicle in the lane.
Crosswind Assist is active at vehicle speeds
above 50 mph (80 km/ h) when driving straight
ahead or cornering gently.
Important safety notes Crosswind Assist does not work if ESP ®
is deac-
tivated or disabled because of a malfunction.
EBD (electronic brake force distribu-
tion)
General information EBD monitors and controls the brake pressure
on the rear wheels to improve driving stability
while braking.
Important safety notes
i Observe the "Important safety notes" sec-
tion ( Y
page 68).
G WARNING
If EBD is malfunctioning, the rear wheels can
lock, e.g. under full braking. This increases the
risk of skidding and an accident.
You should therefore adapt your driving style
to the different handling characteristics. Have
the brake system checked at a qualified spe-
cialist workshop.
Observe information regarding indicator and
warning lamps ( Y
page 289) as well as display
messages ( Y
page 258).
ADAPTIVE BRAKE ADAPTIVE BRAKE enhances braking safety and
offers increased braking comfort. In addition to
the braking function, ADAPTIVE BRAKE also has
the HOLD function ( Y
page 194) and hill start
assist ( Y
page 150).76
Driving safety systems
Safety

SmartKey
Important safety notes
G WARNING
If children are left unsupervised in the vehicle,
they could: R
open the doors, thus endangering other
people or road users. R
get out and disrupt traffic. R
operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they: R
release the parking brake. R
shifting the automatic transmission out of
park position PR
Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
G WARNING
If you attach heavy or large objects to the
SmartKey, the SmartKey could be uninten-
tionally turned in the ignition lock. This could
cause the engine to be switched off. There is a
risk of an accident.
Do not attach any heavy or large objects to the
SmartKey. Remove any bulky key rings before
inserting the SmartKey into the ignition lock.
! Keep the SmartKey away from strong mag-
netic fields. Otherwise, the remote control
function could be affected.
Strong magnetic fields can occur in the vicin-
ity of powerful electrical installations.
Do not keep the SmartKey: R
with electronic devices, e.g. a mobile phone
or another SmartKey. R
with metallic objects, e.g. coins or metal foil. R
inside metallic objects, e.g. a metal case.
This can affect the functionality of the Smart-
Key. Vehicles with KEYLESS-GO start function: do
not keep the SmartKey on the parcel shelf or in
the trunk. Otherwise, the SmartKey may not be
detected, e.g. when starting the engine using
the Start/Stop button.
A check which periodically establishes a radio
connection between the vehicle and the Smart-
Key determines whether a valid SmartKey is in
the vehicle. This occurs, for example: R
when starting the engine R
while driving R
when the external door handles are touched R
during convenience closing
SmartKey functions
C
7 To lock the vehicleD
T To open/close the trunk lid

You will receive visual and acoustic locking con-
firmation if all components were able to be
locked.
When the locator lighting is activated via the
multimedia system, it lights up when it is dark
after the vehicle is unlocked with the SmartKey
(see the Digital Operator's Manual). X
To open the trunk lid automatically from
outside the vehicle: press and hold the T
button until the trunk lid opens. X
To open the trunk lid automatically from
outside the vehicle: if the SmartKey is loca-
ted in the immediate vicinity of the vehicle,
press the T button on the SmartKey.
When the trunk lid closes you can then
release the button.
KEYLESS-GO
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a Smart-
Key in the vehicle.
Locking/unlocking centrally You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry the
SmartKey with you. You can combine the func-
tions of KEYLESS-GO with those of a conven-
tional SmartKey. Unlock the vehicle by using
KEYLESS-GO, for instance, and lock it using the
7 button on the SmartKey.
The driver's door and the door at which the han-
dle is used, must both be closed. The SmartKey
must be outside the vehicle. When locking or
unlocking with KEYLESS-GO, the distance
between the SmartKey and the corresponding
door handle must not be greater than 3 ft (1 m).
A brief radio connection between the vehicle
and the key determines whether a valid Smart-
Key is in, or in the direct vicinity of, the vehicle.
This occurs, for example: R
when starting the engine R
while driving R
when using HANDS-FREE ACCESS R
when the external door handles are touched R
during convenience closing X
To unlock the vehicle: touch the inner sur-
face of the door handle. X
To lock the vehicle: touch sensor surface C
or D .
Make sure that you do not touch the inner
surface of the door handle. X
Convenience closing feature: touch
recessed sensor surface D for an extended
period.
Further information on the convenience clos-
ing feature ( Y
page 96). X
To unlock the trunk lid: pull the handle on
the trunk lid.
Deactivating and activating If you do not intend to use a key for an extended
period of time, you can deactivate the KEYLESS-
GO function of the SmartKey. The SmartKey will
then use very little power, thereby conserving
battery power. For the purposes of activation/
deactivation, the vehicle must not be nearby. X
To deactivate: press the 7 button on the
SmartKey twice in rapid succession.
The battery check lamp of the SmartKey
flashes twice briefly and lights up once, then
KEYLESS-GO is deactivated ( Y
page 84).X
To activate: press any button on the Smart-
Key.
or X
Insert the SmartKey into the ignition lock.
KEYLESS-GO and all of its associated features
are available again.82
SmartKey
Opening and closing