264 Practical hintsWhat to do if …Left display
Right display
Possible cause
Possible solution
# 
Electric consumers
offline!
The consumer battery has insuffi-
cient voltage and can no longer sup-
ply the convenience functions such 
as seat ventilation*.
The electrical consumers will come back online 
as soon as on-board voltage is sufficient.
Battery/Alternator
Stop vehicle!
The battery was charged with a bat-
tery charger or jump started.
The battery is no longer charging. 
Possible causes 
alternator malfunctioning
broken poly-V-belt
Do not forget that the brake system 
requires electrical energy and may 
be operating with restricted capabil-
ity. Considerably greater brake ped-
al force is required and the stopping 
distance is increased.
Have the battery checked at a service sta-
tion. 
Stop immediately and check the poly-V-belt.
If it is broken
Do not continue to drive. Notify an autho-
rized Mercedes-Benz Center.
If it is in order
Drive immediately to the nearest autho-
rized Mercedes-Benz Center. Adjust driv-
ing to be consistent with reduced braking 
responsiveness. 
335 Technical data
Layout of poly-V-belt drive
Layout of poly-V-belt drive
SL 500
1Automatic belt tensioner
2Power steering pump
3Air conditioner compressor
4Crankshaft
5Coolant pump
6Generator (alternator)
7Idler pulley
SL 55 AMGThe SL 55 AMG has two poly-V-belts.1Idler pulley
2Automatic belt tensioner
3Power steering pump
4Air conditioner compressor
5Crankshaft
6Coolant pump
7Generator (alternator)
8Idler pulley
9Automatic belt tensioner
10Super charger 
354 Technical termsMultifunction display
Two display fields in the instrument 
cluster 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/axles
Program mode selector switch
Used to switch the automatic transmis-
sion between standard operation (S) 
and winter operation (W).
SL 55 AMG with steering wheel gear-
shift control and manual shift program: 
in addition to S and W (for regular S or 
winter W operation, see above), you 
can use MANUAL  for manual shift pro-
gramRemote 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.
Retractable hardtop
Hardtop roof that can be opened and 
closed at the push of a button and 
stored in the trunk.
Roll bar
Occupant protection system which 
consists of tubular steel sheathed in 
plastic. The roll bar is lowered into the 
car body during normal driving condi-
tions and raised automatically. It may 
also be manually raised and lowered by 
operating a button during critical driv-
ing situations.