R
It is particularly important to observe the described order when connecting and disconnecting
the jumper cables.
R Never connect or disconnect the battery terminals while the engine is running. G
WARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting the
vehicle or charging the battery, gases can escape from the battery. There is a risk of an explosion.
Allow the frozen battery to thaw out before charging it or jump-starting.
! Avoid repeated and lengthy starting attempts.
Do not use a rapid-charging device to start the engine.
If the indicator/warning lamps do not light up in the instrument cluster at low temperatures, it is very likely that the discharged battery has frozen. In this case you may neither jump-start the vehicle norcharge the battery. The service life of a thawed-out battery may be shorter. Have the thawed-out
battery checked at a qualified specialist workshop.
If the 12 V battery is discharged, or after the vehicle has been jump-started, the Service
Service
Required Required Do
DoNot
Not Shift
Shift Gears
GearsVisit
VisitDealer
Dealer message appears. There is a malfunction in the
on-board voltage. Visit a qualified specialist workshop immediately.
The drive system cannot be started if the 12 V battery is discharged. This is not dependent on
whether the high-voltage battery is charged or not. The vehicle cannot be jump-started if the high-
voltage battery is discharged. The high-voltage battery must be charged first.
The drive system can be started using another vehicle. R Only use batteries with an equal nominal voltage (12 volts).
R Make sure that the battery of the donor vehicle does not have a significantly lower capacity than
the discharged battery.
R Use jumper cables with a sufficient cross-section and insulated terminal clamps from a qualified
specialist workshop, e.g. an authorized Mercedes-Benz Center.
R Make sure that the two vehicles do not touch.
R Route the jumper cables so that they cannot be caught by rotating components in the engine
compartment.
R Do not disconnect the discharged battery from the vehicle's electrical system. 250
Jump-startingBreakdown assistance
