139 Controls in detail
Control system
Control system
The control system is activated as soon 
as the SmartKey in the starter switch is 
turned to position1 or as soon as the 
KEYLESS-GO start/stop button is in 
position 1. The control system enables 
you to
call up information about your vehicle 
change vehicle settings 
For example, you can use the control sys-
tem to find out when your vehicle is next 
due for service, to set the language for 
messages in the instrument cluster dis-
play, and much more.
The control system relays information to 
the multifunction display.
Multifunction display
The multifunction display consists of the 
display fields in the speedometer and the 
tachometer. In its default state, the left 
multifunction display shows the main 
odometer and the outside temperature, 
while the trip odometer appears in the 
right multifunction display. This default 
setting is referred to as the standard 
display.
1Main odometer
2Outside temperature
3Current gear selector lever position
4Trip odometer
5Automatic transmission program mode 
Warning!
G
A driver’s attention to the road and traffic 
conditions must always be his /her primary 
focus when driving. 
For your safety and the safety of others, 
selecting features through the multifunction 
steering wheel should only be done by the 
driver when traffic and road conditions per-
mit it to be done safely.
Bear in mind that at a speed of just 
30 mph (approximately 50 km / h), your 
vehicle is covering a distance of 44 feet 
(approximately 14 m) every second. 
374 Practical hintsWhat to do if …Left display
Right display
Possible cause/consequence
Possible solution
Check doors
2
You are attempting to drive with 
one or more doors open.
Close the doors.
Vehicles with KEYLESS-GO*:
You are pressing the lock button on 
the door handle and at least one 
door is open.
±
Visit
workshop
Certain electronic systems are un-
able to relay information to the con-
trol system. The following systems 
may have failed:
Coolant temperature gauge
Tachometer
Have the electronic systems checked by an 
authorized Mercedes-Benz Center 
(page 336).
Engine
Service
There may be a malfunction in the 
fuel injection system
ignition system
exhaust system
fuel system
Have the engine checked as soon as possible 
by an authorized Mercedes-Benz Center 
(page 336).