2013 MERCEDES-BENZ E-Class CABRIOLET ECU

To ensure that the vehicle is secured against
rolling away unintentionally:
R
the parking brake must be applied.
R the
transmission must be in position P and
the SmartKey must be removed from the
ignition lock.
R on uphill or downhill gradients, the front
wheels must be turned towards the curb. Switching off the engine
Vehicles with automatic transmission X
Apply the parking brake firmly.
X Shift the transmission to position P.
Using the SmartKey
X Turn the SmartKey to position 0 in the
ignition lock and remove it.
The immobilizer is activated.
i The
SmartKey can only be removed if the
transmission is in position P.
Using KEYLESS-GO
X Press the Start/Stop button (Y page
151).
The engine stops and all the indicator
lamps in the instrument cluster go out.
i When the driver's door is closed, this
corresponds

to SmartKey position 1. When
the driver's door is open, it corresponds to
SmartKey position 0 or "SmartKey
removed".
If you try to switch off the engine when the
transmission is not in position P, a message
appears in the multifunction display. A signal
sounds. Parking brake
G
WARNING
If you must brake the vehicle with the parking
brake, the braking distance is considerably
longer

and the wheels could lock. There is an
increased danger of skidding and accidents. Only use the parking brake to brake the
vehicle when the service brake is faulty. Do
not apply the parking brake too firmly. If the
wheels lock, release the parking brake until
the wheels begin turning again.
G
WARNING
If you leave children unsupervised in the
vehicle, they could set it in motion by, for
example:
R releasing the parking brake
R shifting the automatic transmission out of
the parking position P
R starting the engine.
They could also operate the vehicle's
equipment.

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 unsupervised in the vehicle. If you brake the vehicle with the parking
brake, the brake lamps will not light up.
X
To apply:
depress parking brake ; firmly.
When the engine is running, the $ (USA
only) or J (Canada only) indicator lamp
lights up in the instrument cluster.
X To release: depress the brake pedal and
keep it depressed.
X Pull release handle :.
When the ignition is switched on or the
engine is running, the $ (USA only) or
J

(Canada only) indicator lamp goes out
in the instrument cluster. 168
Parking
Driving and parking

DISTRONIC PLUS does not replace the
parking brake and must not be used for
parking.
The DISTRONIC PLUS braking effect is
canceled and the vehicle can start moving if:
R
DISTRONIC PLUS is deactivated using the
cruise control lever.
R you accelerate.
R there is a malfunction in the system or an
interruption in the power supply, e.g.
battery failure.
R the electrical system in the engine
compartment, the battery or the fuses are
tampered with.
R the battery is disconnected.
If you wish to leave the vehicle or park it,
deactivate DISTRONIC PLUS and secure the
vehicle against rolling away.
If DISTRONIC PLUS detects that the vehicle
in
front is stopping, it brakes your vehicle until
it is stationary.
Once your vehicle is stationary, it remains
stationary and you do not need to depress the
brake.
i Depending on the specified minimum
distance, your vehicle will come to a
standstill at a sufficient distance behind the
vehicle in front. The specified minimum
distance is set using the control on the
cruise control lever.
You will see a warning message in the
multifunction display if DISTRONIC PLUS is
activated and:
R the driver's door is open and the driver's
seat belt is unfastened.
R the engine is switched off, unless it is
automatically switched off by the ECO
start/stop function.
R the hood is opened.
Shift to 'P' X
Shift the transmission to position P to
prevent the vehicle from rolling away.
DISTRONIC PLUS is deactivated. The
warning message in the multifunction
display disappears.
The horn will also sound at regular intervals if
DISTRONIC PLUS is activated and you:
R switch the engine off, open the driver's
door and remove your seat belt
R open the hood
The

sounding of the horn alerts you to the fact
that the vehicle has been parked while
DISTRONIC PLUS is still activated. The sound
becomes louder if you attempt to lock the
vehicle. The vehicle is not locked until
DISTRONIC PLUS is deactivated.
i If the engine has been switched off, it
cannot be started again until DISTRONIC
PLUS has been deactivated.
If DISTRONIC PLUS is activated and a
malfunction occurs in the system or if there
is a disruption in the power supply, the
Brake Immediately message is shown in
the multifunction display. Depress the brake
firmly immediately until the warning message
disappears from the multifunction display or
shift the transmission to position P.
DISTRONIC PLUS is then deactivated.
Setting a speed G
WARNING
Keep in mind that it may take a brief moment
until the vehicle has made the necessary
adjustments.
Increase

or decrease the set vehicle speed to
a value that the prevailing road conditions and
legal speed limits permit. Otherwise, sudden
and unexpected acceleration or deceleration
of the vehicle could cause an accident and/
or serious injury to you and others. Driving systems
183
Driving and parking Z

HOLD function
General notes The HOLD function can assist the driver in the
following situations:
R
when pulling away, especially on steep
slopes
R when maneuvering on steep slopes
R when waiting in traffic
The vehicle is kept stationary without the
driver having to depress the brake pedal.
The
braking effect is canceled and the HOLD
function deactivated when you depress the
accelerator pedal to pull away.
Activation conditions You can activate the HOLD function if:
R
the vehicle is stationary.
R the engine is running or if it has been
automatically switched off by the ECO
start/stop function.
R the

driver's door is closed or your seat belt
is fastened.
R the parking brake is released.
R the hood is closed.
R the transmission is in position D, R or N.
R DISTRONIC PLUS is deactivated.
Activating the HOLD function G
WARNING
The vehicle's brakes are applied when the
HOLD function is activated. For this reason,
deactivate

the HOLD function if the vehicle is
to be set in motion by other means (e.g. in a
car wash or by towing). X
Make sure that the activation conditions
are met.
X Depress the brake pedal.
X Quickly depress the brake pedal further
until ë appears in the multifunction
display.
The HOLD function is activated. You can
release the brake pedal.
i If depressing the brake pedal the first
time does not activate the HOLD function,
wait briefly and then try again.
Deactivating the HOLD function G
WARNING
Never get out of the vehicle when the HOLD
function is activated.
The HOLD function must never be operated
or

deactivated by a passenger or from outside
the vehicle.
The HOLD function does not replace the
parking brake and must not be used for
parking.
The braking effect of the HOLD function is
canceled and the vehicle could roll away if:
R the HOLD function is deactivated by
depressing the accelerator pedal or the
brake pedal.
R there is a malfunction in the system or an
interruption in the power supply, e.g.
battery failure.
R the electrical system in the engine
compartment, the battery or the fuses are
tampered with.
R the battery is disconnected.
If you leave the vehicle or park it, deactivate
the HOLD function and secure the vehicle
against rolling away.
The HOLD function is deactivated
automatically if:
R you accelerate and the transmission is in
position D or R.
R you shift the transmission to position P. Driving systems
189
Driving and parking Z

Display messages Possible causes/consequences and
M SolutionsF(USA
only)J(Canada
only)
Please Release
Parking Brake You are driving with the parking brake applied. A warning tone also
sounds.
X
Release the parking brake. $(USA
only)J(Canada
only)
Brake Immediately A malfunction has occurred while the HOLD function or
DISTRONIC PLUS is active.
A
tone may also sound at regular intervals. If you attempt to lock
the vehicle, the tone becomes louder.
You cannot start the engine.
X Paying attention to the traffic situation, immediately depress the
brake pedal firmly and hold until the display message
disappears.
X Secure the vehicle against rolling away ( Y page 167).
You can restart the engine. $(USA
only)J(Canada
only)
Check Brake Fluid
Level There is not enough brake fluid in the brake fluid reservoir.
In addition, the $ (USA only)/J (Canada only) warning
lamp lights up in the instrument cluster and a warning tone
sounds.
G WARNING
The braking effect may be impaired.
There is a risk of an accident.
X Pull over and stop the vehicle safely as soon as possible, paying
attention

to road and traffic conditions. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away ( Y page 167).
X Consult a qualified specialist workshop.
X Do not add brake fluid. This does not correct the malfunction. #
Check Brake Pad
Wear The brake pads/linings have reached their wear limit.
X
Visit a qualified specialist workshop. G
mbrace Inoperative One or more main features of the mbrace system are
malfunctioning.
X
Have the mbrace system checked immediately at a qualified
specialist workshop. Display messages
231
On-board computer and displays Z

Display messages Possible causes/consequences and
M SolutionsPRE-SAFE
Inoperative See
Operator's Manual
Important functions of PRE-SAFE
®
have failed. All other occupant
safety systems, e.g. air bags, remain available.
X Visit a qualified specialist workshop immediately. PRE-SAFE
Functions
Currently Limited
See Operator's
Manual
PRE-SAFE
®

Brake is temporarily inoperative. Possible causes are:
R function is impaired due to heavy rain or snow.
R the sensors in the radiator grill and the bumper are dirty.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
When the causes stated above no longer apply, the display
message disappears.
PRE-SAFE ®
Brake is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 167).
X Clean the sensors in the radiator grill and the bumper
(Y page 304).
X Restart the engine. PRE-SAFE
Functions Limited
See Operator's
Manual
PRE-SAFE
®
Brake is inoperative due to a malfunction. BAS PLUS
or the distance warning signal may also have failed.
X Visit a qualified specialist workshop. A
Malfunction
Service Required G
Risk of injury
Cabriolet: the roll bars are defective.
X Visit a qualified specialist workshop immediately.232
Display messages
On-board computer and displays

Display messages Possible causes/consequences and
M SolutionsFront Passenger
Airbag Enabled
See Operator's
Manual The front-passenger air bag is enabled during the journey, even
though:
R
a child, a small adult or an object weighing less than the
system's weight threshold is located on the front-passenger
seat.
or
R the front-passenger seat is unoccupied.
The system may detect objects or forces applying additional
weight on the seat.
G WARNING
The air bag may deploy unintentionally.
There is an increased risk of injury.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 167).
X Switch the ignition off.
X Open the front-passenger door.
X Remove the child and the child restraint system from the front-
passenger seat.
X Make sure that there are no objects on the seat adding to the
weight.
The system may otherwise detect the additional weight and
interpret the seat occupant's weight as greater than it actually
is.
X Keep the seat unoccupied, close the front-passenger door and
switch on the ignition.
X Observe the ^a indicator lamp in the center console and
the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 45

indicator lamp must light up and remain lit. When
the indicator lamp is on, OCS (Occupant Classification System)
has deactivated the front-passenger air bag ( Y page 46).
R the Front Passenger Airbag Enabled See Operator's
Manual or Front Passenger Airbag Disabled See
Operator's Manual display messages must not be shown in
the multifunction display.
X Wait for a period of at least 60 seconds until the necessary
system checks have been completed.
X Make sure that the display messages do not appear in the
multifunction display.234
Display messages
On-board computer and displays

Display messages Possible causes/consequences and
M SolutionsIf these conditions are fulfilled, the front-passenger seat can be
occupied
again. Whether the 45 indicator lamp remains lit
or goes out depends on how OCS classifies the occupant.
If the conditions are not fulfilled, the system is not operating
correctly.
X Visit a qualified specialist workshop immediately.
For further information about the Occupant Classification System,
see ( Y page 46). Front Passenger
Airbag Disabled
See Operator's
Manual The front-passenger air bag is disabled during the journey, even
though:
R
an adult
or
R a person larger than a certain size is occupying the front-
passenger seat.
If additional forces are applied to the seat, the system may
interpret the occupant's weight as lower than it actually is.
G WARNING
The front-passenger air bag does not deploy during an accident.
There is an increased risk of injury.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 167).
X Switch the ignition off.
X Have the occupant get out of the vehicle.
X Keep the seat unoccupied, close the front-passenger door and
switch on the ignition.
X Observe the 45
indicator lamp in the center console and
the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 45

indicator lamp must light up and remain lit. When
the indicator lamp is on, OCS has deactivated the front-
passenger air bag ( Y page 46).
R the Front Passenger Airbag Enabled See Operator's
Manual or Front Passenger Airbag Disabled See
Operator's Manual display messages must not be shown in
the multifunction display.
X Wait for a period of at least 60 seconds until the necessary
system checks have been completed.
X Make sure that the display messages do not appear in the
multifunction display. Display messages
235
On-board computer and displays Z

Engine
Display messages Possible causes/consequences and
M Solutions+
Check Coolant
Level See
Operator's Manual The coolant level is too low.
!
Avoid
making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
X Add coolant, observing the warning notes before doing so
(Y page 296).
X If coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist
workshop. ? The fan motor is faulty.
X
At coolant temperatures under 248 ‡(120 †),
drive to the next
qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic. ?
Coolant Too Hot
Stop Vehicle Turn
Engine Off The coolant is too hot.
A warning tone also sounds.
G WARNING
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away ( Y page 167).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the display message goes out
and the coolant temperature is under 248 ‡ (120

†).
Otherwise, the engine could be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to
248 ‡ (120 †).240
Display messages
On-board computer and displays