326 Practical hintsWhat to do if …?Symbol messagesDisplay symbol
Display message
Possible cause
Possible solution
#
Undervoltage
Charge battery
The battery has insufficient voltage.
Start the engine (
page 43).
Undervoltage
Switch off
consumers
The battery has insufficient voltage.
Turn off unnecessary electrical con-
sumers.
VISIT WORKSHOP!
The battery was charged with a battery 
charger or jump started.
Have the battery checked at a service 
station. 
The battery is no longer charging.
Possible causes:
alternator malfunctioning
broken poly-V-belt
Stop immediately and check the 
poly-V-belt.
If it is broken:
Do not continue to drive. Otherwise 
the engine will overheat due to an in-
operative water pump which may re-
sult in damage to the engine. Notify an 
authorized Mercedes-Benz Center.
If it is intact:
Drive immediately to the nearest au-
thorized Mercedes-Benz Center. Ad-
just driving to be consistent with 
reduced braking responsiveness. 
423 Technical terms
Overspeed range
Engine speeds within the red marking 
on the tachometer dial. Avoid this en-
g ine s pe ed r ang e, a s it  ma y r es ult i n se -
rious engine damage that is not 
covered by the Mercedes-Benz Limited 
Warranty.
Parktronic (Parking assist)*
System which uses visual and acoustic 
signals to assist the driver during park-
ing maneuvers.
Poly-V-belt drive
Drives engine-components (alternator, 
AC compressor, etc.) from the engine.Power train
Collective term designating all compo-
nents used to generate and transmit 
motive power to the drive axles, includ-
ing
engine
clutch/torque converter
transmission
transfer case
drive shaft
differential
axle shafts/axlesProgram mode selector switch
Used to switch the automatic transmis-
sion between regular operationS and 
comfort operationC.
CLK 55 AMG with steering wheel gear-
shift control and manual shift program: 
In addition toS andC (for regularS or 
comfortC operation, see above) you 
can use theM for manual shift 
program.