Page 203 of 474
202 Controls in detailAudio systemButton and soft key operation
In these instructions, the alphanumeric 
keypad (right side of radio panel) and the 
function buttons (left side of radio panel) 
are referred to as “buttons”. The four keys 
below the display panel are referred to as 
“soft keys”.
Operation
Switching the unit on/off
Switching on
Turn the SmartKey in the starter switch 
to position1 or2. 
If the audio system was on as you 
removed the SmartKey from the starter 
switch, the audio system will 
automatically come back on as you 
turn the SmartKey to position1 or2.
or
Press M button.
!Do not press directly in the display 
face. Otherwise, the display will be 
damaged.
iIf the radio is switched on without the 
key in the starter switch, it will 
automatically switch off again after 
approx. 30 minutes.
If your vehicle is equipped with a 
telephone, the display may prompt you 
to enter your PIN (GSM network) or 
code (TDMA or CDMA network). 
         
        
        
     
        
        Page 204 of 474

203 Controls in detail
Audio system
Switching off
Remove SmartKey from starter switch.
or
Press M button.
Adjusting the volume
Turn rotary control of N button.
The volume will increase or decrease 
depending on the direction turned.Adjusting sound functions
The bass and treble functions are called up 
by pressing the O button.
Settings for bass and treble are stored 
separately for the AM and FM wavebands, 
weather band, CD mode and telephone 
mode.
Bass
Press O button repeatedly until BASS
 appears in the display.
Press 
+ or
– soft key to increase or 
decrease tone level accordingly.
or
Press 
RES
 soft key briefly to reset bass 
tones to their center level.
The radio switches back to the 
standard radio menu 8 seconds after 
the last soft key is pressed.
iShould excessively high temperatures 
occur while the audio system is being 
operated, the display will dim. If tem-
peratures continue to rise, 
HIGH TEMP
 
will appear in the display, after which 
the audio system will be switched off 
for a cooling-down period.
iIf your vehicle equipment includes a 
Mercedes-Benz specified mobile 
telephone*, you can adjust its volume 
separately from the volume of the 
audio system while the telephone is 
being used. 
         
        
        
     
        
        Page 205 of 474

204 Controls in detailAudio systemAdjusting treble
Press O button repeatedly until TREBLE
 appears in the display.
Press 
+ or
– soft key to increase or 
decrease tone level accordingly.
or
Press 
RES
 soft key briefly to reset treble 
tones to their center level.
The radio switches back to the 
standard radio menu 8 seconds after 
the last soft key is pressed.Sound system*
You can either program the sound settings 
manually (
page 203) or choose settings 
via preset sound characteristics.
You can select from among the following 
settings:
STANDARD
: conventional stereo sound.
SURROUND
: the sound is set for better 
three-dimensional acoustic character-
istics.
SPEECH
: the sound is optimized for the 
spoken word.
Press O button repeatedly until STANDARD
, SURROUND
, or 
SPEECH
 appears 
in the display.
Press X or Y soft key repeatedly 
until the desired sound setting has 
been reached.
The sound is set accordingly.
or
Press 
RES
 soft key briefly.
The sound setting is reset depending 
on the sound source activated.
Radio mode: 
STANDARD
CD/AUX mode: 
SURROUND
Telephone: 
SPEECH
The radio switches back to the 
standard radio menu 8 seconds after 
the last soft key is pressed. 
         
        
        
     
        
        Page 206 of 474

205 Controls in detail
Audio system
Returning sound functions to factory 
settings
Press O button to call up settings 
menu in the display.
Press 
RES
 soft key briefly; the respec-
tive sound function is reset to its center 
level.
or
Press and hold 
RES
 soft key until 
RESET
 
appears in the display.
The sound settings for bass and treble 
are returned to their center level and 
the volume is set to a predefined level.Vehicles with sound system*:
The sound setting is reset depending 
on the sound source activated.
Radio mode: 
STANDARD
CD/AUX mode: 
SURROUND
Telephone: 
SPEECH
The radio switches back to the 
standard radio menu 4 seconds 
after the last soft key is pressed.
Adjusting volume distribution
Call up fader and balance functions by 
pressing the P button.
Fader
Press P button repeatedly until FADER
 appears in the display.
Press V or W soft key.
The volume is distributed accordingly 
between the front and rear of the 
vehicle.
or
Press 
RES
 soft key briefly.
The fader is reset to its center level.
The radio switches back to the 
standard radio menu 8 seconds after 
the last soft key is pressed. 
         
        
        
     
        
        Page 207 of 474

206 Controls in detailAudio systemAdjusting balance
Press P button repeatedly until BALANCE
 appears in the display.
Press X or Y soft key.
The volume is distributed between the 
left and right sides of the vehicle.
or
Press 
RES
 soft key briefly.
The balance is reset to its center level.
The radio switches back to the 
standard radio menu 8 seconds after 
the last button is pressed.Returning volume distribution to 
factory settings
Press P button to call up settings 
menu in the display.
Press 
RES
 soft key briefly; the 
respective volume distribution is reset 
to its center (flat) level.
or
Press and hold 
RES
 soft key until 
RESET
 
appears in the display.
The volume distribution settings for 
fader and balance are set to their 
center level.
The radio switches back to the 
standard radio menu 4 seconds after 
the last soft key is pressed.Telephone* muting
If your vehicle equipment includes a 
Mercedes-Benz specified mobile 
telephone*, you can adjust its volume 
separately from the volume of the audio 
system while the telephone is being used. 
         
        
        
     
        
        Page 208 of 474

207 Controls in detail
Audio system
Connecting an external audio source 
(AUX) to the radio*
An optional dealer-installed cinch-connec-
tor* for connecting an external audio 
source may become available for your 
vehicle model. Feature description is 
based on preliminary information at time 
of printing. Contact an authorized 
Mercedes-Benz Center for availability.
You can adjust the volume (
page 203), 
the sound settings (
page 203) and the 
volume distribution (page 205) for the 
AUX input.
Calling up AUX mode
Press and hold Q button until AUX 
appears in the display.
Canceling AUX mode
Press any audio source button.
Radio operation
Selecting radio mode
Press b button.
Calling up wavebands
You can choose from among the FM, AM, 
and WB wavebands.
Weather band (
page 210).Calling up wavebands for radios 
without SAT
Press 
FM or 
AM soft key to switch 
between FM and AM.
The FM and AM wavebands are called 
up one after another.
or
Press 
WB soft key.
The weather band menu is called up.
The waveband currently selected 
appears in the upper left-hand corner 
of the display.
iFM waveband: 87.7......107.9 MHz
AM waveband: 530......1 710 KHz 
         
        
        
     
        
        Page 209 of 474
208 Controls in detailAudio systemCalling up wavebands for radios 
with SAT
Press 
FM, AM, or 
WB soft key repeatedly 
until desired waveband has been 
selected.
The FM, AM, and WB wavebands are 
called up one after another.
The waveband currently selected 
appears in the upper left-hand corner 
of the display.Selecting a station
The following options are available for 
selecting a station:
Direct frequency input (
page 208)
Manual tuning (
page 209)
Automatic seek tuning (
page 209)
Scan search (
page 209)
Station memory (
page 209)
Automatic station memory (Autostore) 
(page 210)
The station search proceeds in the 
following frequency increments:
200 kHz in FM range
10 kHz in AM rangeDirect frequency input
Select desired waveband.
Press * button.
Enter desired frequency with 
buttons1to R.iYou can only enter frequencies within 
the respective waveband.
If a button is not pressed within 
4 seconds, the radio will return to the 
last station tuned. 
         
        
        
     
        
        Page 210 of 474

209 Controls in detail
Audio system
Manual tuning
Select desired waveband.
Press S or Tbutton for approx. 
3 seconds.
Press button repeatedly until desired 
frequency has been reached.
Step-by-step station tuning takes place 
in ascending or descending order. Each 
time the button is pressed, the radio 
tunes further by 0.2 MHz. During 
manual tuning, the radio is muted.
Automatic seek tuning
Select desired waveband.
Press S or T button briefly.
The radio will tune to the next highest 
or next lowest receivable frequency.Scan search
Starting scan search
Select desired waveband.
Press 
SC soft key.
SC will appear in the display. The 
radio briefly tunes in all receivable 
stations on the waveband selected.
Ending scan search
Press 
SC soft key or S or T.
The station last played will be 
selected and 
SC disappears from 
the display.Station memory
You can store ten AM and ten FM stations 
in the memory.
Storing stations
Tune in desired station.
Press and hold desired station 
button1 to R until a brief 
signal tone is heard.
The frequency is stored on the 
selected station button.
Calling up stations
Press desired station button1 
to R briefly.
iIf no station is received after two 
consecutive scans of the complete 
frequency range, then the scan stops 
at the frequency from which it began.