655 Practical hints
What 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 and 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. 
658 Practical hintsWhat to do if …?Display 
Possible cause/consequence
Possible solution
Coolant Low
Stop Vehicle
Turn Engine Off
The poly-V-belt could be broken.
Stop the vehicle in a safe location or as soon 
as it is safe to do so and immediately turn off 
the engine.
Engage the electronic parking brake 
(page 412).
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:
Do not continue to drive the vehicle with this 
message displayed. Doing so could result in 
serious engine damage that is not covered by 
the Mercedes-Benz Limited Warranty.
Observe the coolant temperature gauge in 
the instrument cluster (
page 30).
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