Starting procedure with the SmartKey
To start the engine using the SmartKey instead of KEYLESS-GO, pull the Start/ Stop button out of the ignition lock.
•► To start a gasoline engine: turn the SmartKey to position 3 in the ignition lock and release it as soon as the engine is running.
•► To start a diesel engine: turn the SmartKey to position 2 in the ignition lock.
http://strategic-human-resource.com/The 
preglow indicator lamp in the
instrument cluster lights up.
•► When the 
preglow indicator lamp
goes out, turn the SmartKey to position 3 and release it as soon as the
engine is running.
You can start the engine without preglow if the engine is warm.
See also:
Limiting the opening angle of thetailgate
Important safety notes
You can limit the opening angle of the tailgate
in the top half of its opening range. This could
be useful, for example, if there is insufficient
space above the tailgate.
...
Problems with your vehicle
If you should experience a problem with your
vehicle, particularly one that you believe may
affect its safe operation, we urge you to
contact an authorized Mercedes-Benz Center
immediately to have ...
Comfort on long journeys as standard: the front seats
The seats in the Mercedes-Benz C-Class make a valuable contribution to
comfort on long journeys. As an optional extra, climatised seats are now
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