304 Practical hintsWhat to do if …?Symbol messagesDisplay symbol
Display messages
Possible cause
Possible solution
#
BATTERY/ALTERNATOR
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 inoperative 
water pump which may result in damage 
to the engine. Notify an authorized 
Mercedes-Benz Center.
If it is intact:
Drive immediately to the nearest autho-
rized Mercedes-Benz Center. Adjust driv-
ing to be consistent with reduced braking 
responsiveness. 
363 Technical data
Layout of poly-V-belt drive
Layout of poly-V-belt drive
CL 500
1Automatic belt tensioner
2ABC tandem pump (pump for 
power-steering assistance and ABC 
chassis)
3Air conditioning compressor
4Crankshaft
5Coolant pump
6Generator (alternator)
7Idler pulley
CL 55 AMGThe CL 55 AMG has two poly-V-belts (belt 
one shown in purple/belt two shown in 
black).1Idler pulley
2Automatic belt tensioner
3ABC tandem pump (pump for 
power-steering assistance and ABC 
chassis)
4Air conditioning compressor
5Crankshaft
6Coolant pump
7Generator (alternator)
8Idler pulley
9Automatic belt tensioner
aSupercharger
CL 600
1Automatic belt tensioner
2ABC tandem pump (pump for 
power-steering assistance and ABC 
chassis)
3Air conditioning compressor
4Crankshaft
5Coolant pump
6Generator (alternator)
7Idler pulley
8Idler pulley
9Idler pulley 
386 Technical termsMultifunction display
Display field in the speedometer used 
to present information provided by the 
control system.
Multifunction steering wheel
Steering wheel with buttons for operat-
ing the control system.
Overspeed range
Engine speeds within the red marking 
of the tachometer dial. Avoid this en-
gine speed range, as it may result in se-
rious engine damage that is not 
covered by the Mercedes-Benz Limited 
Warranty.
Parktronic*
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 sport operationS and 
comfort operationC.
CL 55 AMG with steering wheel gear-
shift control and manual shift program: 
in addition toS andC (see above), you 
can use theM for manual operation.
Remote Vehicle Diagnostics
Transmission of vehicle data and cur-
rent location to the Mercedes-Benz 
Customer Assistance Center for sub-
scribers to Tele Aid service.
REST
(Residual engine heat utilization)
Feature that uses the engine heat 
stored in the coolant to heat the vehi-
cle interior for a short time after the en-
gine has been turned off.
Restraint systems
Seat belts, belt tensioners, airbags and 
child restraint systems. As indepen-
dent systems, their protective func-
tions complement one another.