alternator belt MERCEDES-BENZ S-Class 2008 W221 Comand Manual

678 Practical hintsWhat to do if …?Display
Possible cause/consequence
Possible solution
The battery is no longer charging.
Possible causes:

alternator malfunctioning


broken poly-V-belt

Stop the vehicle immediately in a safe loca-
tion.

Engage the electronic parking brake
(page 422).

Check the poly-V-belt.
If it is broken:

Do not continue to drive. Otherwise the en-
gine will overheat due to an inoperative water
pump which may result in damage to the en-
gine.

Notify an authorized Mercedes-Benz Center.
If it is intact:

Drive immediately to the nearest authorized
Mercedes-Benz Center.
There is a malfunction in the electronic
system.

Have the system checked by an authorized
Mercedes-Benz Center as soon as possible.

750 Technical dataLayout of poly-V-belt driveS 450 4MATIC
1, S 550 and
S 550 4MATIC
1Idler pulley
2Idler pulley
3Automatic belt tensioner
4Pump for power-steering assistance
Vehicles with ABC*: ABC* tandem
pump (pump for power-steering assis-
tance and ABC* chassis)
5Air conditioning compressor
6Crankshaft
7Coolant pump
8Generator (alternator)
S63 AMG
1Idler pulley
2Idler pulley
3Idler pulley
4Automatic belt tensioner
5Pump for power-steering assistance
6Air conditioning compressor
7Crankshaft
8Coolant pump
9Generator (alternator)
S 600 and S 65 AMG
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
1Canada only