
Problems with the key/remote control
Problem Possible causes/consequences and
0050
0050Solutions It is no longer possible
to lock the vehicle
using the remote
control.
The turn signals do not
flash when the vehicle
is locked. The doors are not closed properly.
X
Close the doors properly and lock the vehicle again. The central locking system has malfunctioned.
X
Lock the vehicle using the folding key (Y page 66).
X Have the central locking system checked as soon as possible
at a qualified specialist workshop. It is no longer possible
to lock or unlock the
vehicle using the
remote control. The key battery is weak or discharged.
X
Point the remote control at the driver's door handle from very
close range and press the 0036or0037 button.
If this does not work:
X Replace the key battery (Y page 69).
Or
X Lock the vehicle using the folding key (Y page 66). The remote control is faulty.
X
Lock the vehicle using the folding key (Y page 66).
X Have the key checked at a qualified specialist workshop. The key cannot be
turned in the ignition
lock. The steering lock has jammed mechanically.
X
Remove the key and insert it again into the ignition lock. Turn
the steering wheel from side to side while doing so. The engine cannot be
started using the key. The on-board voltage is too low.
X Switch off all non-essential consumers, such as interior lighting,
and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 266).
Or
X Jump-start the vehicle (Y page 278).
Or
X Consult a qualified specialist workshop. You have lost a key. X
Have the key deactivated at a qualified specialist workshop.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the mechanical locks replaced. 70
KeyOpening and closing 

X
To open: for the right-hand side of the vehi-
cle, turn thumbwheel 0044or for the left-hand
side of the vehicle, thumbwheel 0043of the
air vents clockwise.
X To close: for the right-hand side of the
vehicle, turn thumbwheel 0044or for the left-
hand side of the vehicle, thumbwheel 0043of
the air vents counter-clockwise. Adjusting the air vents in the roof duct
! Always leave at least one air vent open.
If the rear-compartment air conditioning is
switched on and all the air vents are closed,
the air-conditioning system may be dam-
aged. On vehicles with rear-compartment air con-
ditioning, adjustable air vents are integrated
into the roof duct.
X To adjust the airflow: open or close the
air flap in air vents 0043as needed.
X To adjust the air distribution: turn air
vent 0043to the desired position. Operating the auxiliary heating sys-
tem Important safety notes
G
DANGER
If the exhaust pipe is blocked or adequate
ventilation is not possible, poisonous gases
such as carbon monoxide (CO) may enter the vehicle. This is the case, for example in
enclosed spaces or if the vehicle gets stuck
in snow. There is a risk of fatal injury.
Switch the auxiliary heating off in enclosed
spaces without extraction systems, e.g. in
garages. If the vehicle is stuck in snow and
you have to leave the auxiliary heating run-
ning, keep the exhaust pipe and the area
around the vehicle free of snow. To ensure an
adequate supply of fresh air, open a window
on the side of the vehicle that is not facing
into the wind. G
WARNING
When the auxiliary heating is switched on,
parts of the vehicle can become very hot, e.g.
the exhaust system. Flammable material such
as leaves, grass or twigs may ignite if they
come into contact with hot parts of the
exhaust system. There is a risk of fire.
When the auxiliary heating is switched on,
make sure that no flammable material can
come into contact with hot vehicle compo-
nents.
! Turn on the auxiliary heating at least once
a month for approximately 10 minutes. The
auxiliary heating could otherwise be dam-
aged.
! Make sure that the flow of hot air is not
blocked. The auxiliary heating will other-
wise overheat and switch off.
Your vehicle may be equipped with either an
auxiliary hot-water heater or an auxiliary
warm-air heater. Adjustment and operation of
the:
R hot-water auxiliary heater is done via the
on-board computer and with the auxiliary
heating button in the control panel
(Y page 124) or with the remote control
(Y page 125).
R auxiliary warm-air heater is done via the
timer above the overhead control panel
(Y page 127).
The auxiliary heating works independently of
the engine and supplements the climate 122
Operating the auxiliary heating systemClimate control 

X
Use the 0081or0082 button on the steer-
ing wheel to select the desired switch-on
time.
Use the Timer off
Timer off setting to deactivate
automatic switch-on.
X Press the 0080button on the steering
wheel.
The switch-on time is selected. The yellow
indicator lamp in the 0084button lights up. Setting the switch-on time
X Use the same method to select a switch-on
time as described in the "Preselecting a
switch-on time" section.
On-board computer without steering
wheel buttons
X Press the 0045reset button on the instru-
ment cluster.
The hour display flashes.
X Use the 0074and 0075buttons on the instru-
ment cluster to set the hours.
X Press reset button 0045.
The minute display flashes.
X Use the 0074and 0075buttons to set the
minutes.
The switch-on time is set and selected.
On-board computer with steering wheel
buttons
X Press the 0041button on the steering
wheel.
The display shows the Hours
Hours menu.
X Use the 0081and0082 buttons on the
steering wheel to set the hours.
X Press the 0041button.
The display shows the Minutes
Minutes menu.
X Use the 0081and0082 buttons to set the
minutes.
X Press the 0080button.
The switch-on time is set and selected. Operation with the remote control
Important information You can switch the auxiliary heating on/off
and set the operating duration using the
remote control. You can use up to 4 remote
control units on the vehicle. These must be
synchronized for the receiver in your vehicle
(Y
page 126).
The remote control has a maximum range of
approximately 600 meters. This range is
reduced by:
R sources of interference
R solid objects between the remote control
and the vehicle
R the remote control being in an unfavorable
position in relation to the vehicle
R transmitting from an enclosed space
Overview of the remote control 0043
Indicator lamp
0044 To confirm settings
0087 To switch the remote control on/off, set
the operating duration or end or cancel
settings
Indicator lamp 0043lights up in various ways to
show different operating modes: Signaling Meaning
Lights up red Remote control switched
on
Data transferOperating the auxiliary heating system
125Climate control Z 

Signaling Meaning
Flashes red Auxiliary heating switched
off
Lights up
green Auxiliary heating switched
on
Flashes green Change operating duration
active
Flashes alter-
nately red and
green Remote control in syn-
chronizing mode
i
When the remote control battery is weak,
indicator lamp 0043flashes red rapidly.
Replace the remote control battery
(Y page 130).
You can find further information on the lamp
status in the "Problems with the auxiliary
heating" section (Y page 132).
Switching the remote control on/off The remote control switches to standby mode
after 10 seconds. Indicator lamp 0043goes out.
X To switch on: press and hold the 00D0
button until indicator lamp 0043lights up red.
If a connection between the remote control
and the receiver in the vehicle has been
established and indicator lamp 0043:
R flashes red, the auxiliary heating is
switched off.
R lights up green, the auxiliary heating is
switched on.
X To switch off: press and hold the 00D0
button until indicator lamp 0043goes out.
Switching the auxiliary heating on/off X
Switch on the remote control.
X To switch on: when indicator lamp 0043
flashes red, press the 0070button.
During data transmission, indicator
lamp 0043lights up red. When indicator lamp
0043lights up green, the
auxiliary heating is switched on.
X To switch off: when indicator lamp 0043
lights up green, press the 0070button.
During data transmission, indicator
lamp 0043lights up red.
When indicator lamp 0043flashes red, the
auxiliary heating is switched off.
Changing the operating duration X
Switch on the remote control.
X When indicator lamp 0043flashes red, press
00D0 and0070 simultaneously.
Indicator lamp 0043flashes green.
X Press the 00D0button repeatedly until the
desired operating duration is shown.
R 20 minutes
Indicator lamp 0043flashes green twice.
R 30 minutes
Indicator lamp 0043flashes green three
times.
R 40 minutes
Indicator lamp 0043flashes green four
times.
X Press the 0070button.
During data transmission, indicator
lamp 0043lights up red.
If indicator lamp 0043emits two long, green
flashes, the selected operating duration is
stored.
i If no adjustment is made, indicator
lamp 0043flashes six times and the remote
control goes into standby mode.
Synchronizing the remote control X
Press the 0084auxiliary heating button in
the control panel (Y page 124) for longer
than 10 seconds.
When you press and hold the 0084button,
the red indicator lamp lights up in the but-
ton. 126
Operating the auxiliary heating systemClimate control 

When the red indicator lamp in the
0084
button flashes, the receiver in the vehicle
is ready for synchronizing.
X Press and hold the 00D0remote control
button until indicator lamp 0043lights up red.
If there is an active connection between the
remote control and the receiver, indicator
lamp 0043flashes alternately red and green.
The remote control is in synchronizing
mode.
i If you press the 00D0button again on the
remote control after starting synchroniza-
tion, you will only synchronize this remote
control unit with the receiver. Any other
remote control units that were synchron-
ized will be cleared. Indicator lamp 0043
flashes alternately red and green (very
slowly).
X Press the 0070button on the remote
control.
During data transmission, indicator
lamp 0043lights up red.
When remote control indicator lamp 0043
emits two long green flashes, the selected
operating time is synchronized. The indica-
tor lamp in the 0084auxiliary heating but-
ton goes out. Operation with the timer
Important safety notes This is only for vehicles with a hot-water aux-
iliary heater.
G
DANGER
If a switch-on time has been selected, the
auxiliary heating switches on automatically.
R If the ventilation is insufficient, poisonous
exhaust gases can collect, in particular car-
bon monoxide. This is the case in enclosed spaces, for example. There is a risk of fatal
injuries.
R If highly flammable substances or flamma-
ble materials are nearby, there is a risk of
a risk of fire and explosion.
Always deactivate the preselected switch-on
times if you stop the vehicle in such or similar
situations.
Use the timer to:
R activate/deactivate immediate heating
mode
R set up to three switch-on times
R set the operating duration from 10to
120 minutes or to continuous operation
R set the heating level (preselected temper-
ature) to a range between 10 and 30
Timer overview Timer above the overhead control panel
0043
Program column
0059 Sets preselection memory 1 – 3
(Y page 129)
Sets weekday (Mon. – Sun.)
(Y page 128)
0044 Menu bar
0084 Activates/deactivates immediate
heating mode (Y page 128)
0045 Sets the program times
(Y page 129)
0045 Sets the day, time and the operating
duration (Y page 128)
00D1 Sets the heating level
(Y page 130) Operating the auxiliary heating system
127Climate control Z 

If the
0084 symbol in the status bar is shown:
X Press the 00CFor00DB button until the
off
off message in the display panel is shown.
X Press the 0070button.
The preselection time is deactivated. The
time is shown.
Setting the heating level You can set the heating level to a range
between 10 and 30.
The heating level corresponds to a preselec-
tion temperature for the vehicle interior. This
is a guide value and may, depending on the
outside temperature, differ from the actual
vehicle interior temperature.
X Press the 00CFor00DB button until the
00D1 symbol in the menu bar flashes.
X Press the 0070button.
The heating level display flashes.
X Using the 00CFand00DB buttons, set the
desired heating level to a range between 10
and 30.
X Press the 0070button.
The heating level is set and the 0084sym-
bol appears. Switching the heater booster function
on/off Vehicles with auxiliary heating Vehicles with heater booster function
At outside temperatures of up to 39 ‡
(4†)
the fuel-fired heater booster system heats the
vehicle interior as quickly as possible when
the engine is running.
The auxiliary heating automatically switches
to heater booster mode after the engine is
started.
At an outside temperature above 39 ‡ (4†)
the auxiliary heating system and the heater
booster function switch off automatically.
If you switch off the engine without switching
off the heater booster function, the system
will be switched on the next time the engine
is started (memory function).
i Switch the auxiliary heating on or off with
the 0084 button (Y page 124).
X To switch on/off: press the006Aswitch.
If the indicator lamp in the button lights up,
the heater booster function is switched on.
After switching off, the auxiliary heating oper-
ates for about another 2 minutes and then
switches off automatically. Replacing the remote control battery
G
WARNING
Batteries contain toxic and corrosive substan-
ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatal
injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately. 130
Operating the auxiliary heating systemClimate control 

H
Environmental 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.
If the indicator lamp on the remote control
flashes red rapidly, the remote control battery
is discharged. You should replace the remote
control battery.
You need a battery of the type CR2430, which
can be obtained at any qualified specialist
workshop. X
Remove battery cover 0044using a suitable
implement, e.g. a coin, by turning it coun-
ter-clockwise.
X Check the seal on battery cover 0044for
damage and, if necessary, replace.
X Remove old batteries 0087.
X Insert new, clean battery 0087into the bat-
tery tray with the positive pole facing
upwards. Use a lint-free cloth to do so. X
Position battery cover 0044so that mark 0043
on the raised area points between two
recesses 0085.
X Turn battery cover 0044using a suitable
implement, e.g. a coin, clockwise to the
stop.
X Check all the functions of the remote
control (Y page 125). Operating the auxiliary heating system
131Climate control Z 

Problems with the auxiliary heating
Problem Possible causes/consequences and
0050
0050Solutions The indicator lamp on
the remote control
flashes red rapidly. The remote control battery is discharged. Data transmission is not
possible.
X
Replace the remote control battery (Y page 130).The indicator lamp on
the remote control
flashes red and green in
rapid succession. There is no connection between the remote control and the
receiver in the vehicle.
X
Change your position in relation to the vehicle, e.g. hold the
remote control higher or to the side.
X Move closer.
If you cannot establish a connection and the auxiliary heating is
switched on, it can then only be deactivated using the 0084button
(Y page 124). The indicator lamp on
the remote control
flashes red and green in
rapid succession. Several remote controls are being used at the same time.
X
Switch on the remote control again after a short while
(Y page 126). The indicator lamp on
the remote control
flashes red and green in
rapid succession. The remote control is not synchronized.
X
Synchronize the remote control (Y page 126).The indicator lamp on
the remote control
slowly flashes red and
green alternately. The remote control is being synchronized.
X
Wait until the remote control synchronization process is com-
plete (Y page 126). The remote control for
the auxiliary heating
cannot be switched on. The remote control battery is discharged.
X
Replace the remote control battery (Y page 130).The auxiliary heating
does not switch on. The outside temperature is above 39
‡(4 †). The auxiliary heating
switches off automatically. The auxiliary heating
switches off automati-
cally and/or cannot be
switched on. The fuel tank is less than
00C4full. The auxiliary heating switches off
automatically.
X Refuel at the nearest gas station.
X Then, start the auxiliary heating several times until the fuel lines
are full. 132
Operating the auxiliary heating systemClimate control