Mercedes-Benz C-Class Coupe 2019 Operator's Manual page 367

* NOTE Damage to the battery from over‐
voltage
When charging using a battery charger with‐
out a maximum charging voltage, the battery
or the on-board electronics may be damaged.
Only use battery chargers with a maxi‐
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mum charging voltage of 14.4 V.
All other vehicles
When charging the battery and during starting
assistance, always use the jump-start connec‐
tion point in the engine compartment.
* NOTE Damaging the battery through
overvoltage
When charging using a battery charger with‐
out a maximum charging voltage, the battery
or the vehicle electronics may be damaged.
Only use battery chargers with a maxi‐
#
mum charging voltage of 14.8 V.
& WARNING Risk of explosion from hydro‐
gen gas igniting
A battery generates hydrogen gas during the
charging process. If there is a short circuit or
sparks start to form, there is a danger of the
hydrogen gas igniting.
Make sure that the positive terminal of
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the connected battery does not come
into contact with vehicle parts.
Never place metal objects or tools on a
#
battery.
When connecting and disconnecting the
#
battery, you must observe the descri‐
bed order for the battery clamps.
When giving starting assistance, always
#
make sure that you only connect bat‐
tery terminals with identical polarity.
During starting assistance, you must
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observe the described order for con‐
necting and disconnecting the jumper
cables.
Do not connect or disconnect the bat‐
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tery clamps while the engine is running.
Breakdown assistance 365
& WARNING Risk of explosion during
charging process and starting assistance
During the charging process and starting
assistance, the battery may release an explo‐
sive gas mixture.
Avoid fire, open flames, creating sparks
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and smoking.
Make sure that there is sufficient venti‐
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lation during the charging process and
during starting assistance.
Do not lean over a battery.
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& WARNING Risk of explosion from a fro‐
zen battery
A discharged battery may freeze at tempera‐
tures slightly above or below freezing point.
During starting assistance or battery charg‐
ing, battery gas may be released.
Always thaw a frozen battery out first
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before charging it or performing start‐
ing assistance.