Note■The battery acid level is also checked regularly by a specialist garage as part
of the inspection service.■
For technical reasons, on vehicles with the description “AGM”, the electrolyte
level cannot be checked.
Charging
Read and observe
and on page 200 first.
A properly charged vehicle battery is essential for reliably starting the engine.
A charging operation can be performed if the following conditions are satis-
fied.
The engine is turned off.
The ignition is switched off.
All consumers are turned off.
The bonnet is open.
“Fast charging” with high currents
›
Disconnect both battery cables (first of all “negative”, then “positive”).
›
Attach the terminal clamps of the charger to the battery terminals (red =
“positive”, black = “negative”).
›
Plug the mains cable of the charger into the power socket and switch on the
device.
›
After charging has been successful: Switch off the charger and remove the
mains cable from the power socket.
›
Only then disconnect the charger's terminal clamps.
›
Reconnect the cables to the battery (first of all “positive”, then “negative”).
Charging with low voltages
It is not necessary to disconnect the cables from the battery if you recharge
the vehicle battery, for example from a mini-charger.
Refer to the instructions of the charger manufacturer .
A charging current of 0.1 multiple of the total vehicle battery capacity (or low-
er) must be used until full charging is achieved.
The vent plugs of the vehicle battery should not be opened for charging.
WARNING■ When you charge a battery, hydrogen is released, and a highly explosive
gas mixture is also produced. An explosion can be caused through sparkling
over during unclamping or loosening of the cable plug while the ignition is
on.■
Creating a bridge between the poles on the battery (e.g. with metal ob-
jects - cables) creates a short circuit - risk of damage to the battery, explo-
sion and burning of the battery, jets of acid spurting out.
■
Avoid creating sparks when working with cables and electrical devices.
Strong sparking represents a risk of injury.
■
Before carrying out any work on the electrical system, switch off the en-
gine, the ignition and all electrical components and disconnect the negative
terminal
.
■
“Quick-charging” the vehicle battery is dangerous and requires a special
charger and specialist knowledge.
■
We therefore recommend that vehicle batteries be “rapidly charged” by a
specialist garage.
CAUTION
On vehicles with the START/STOP system or additional heating (auxiliary heat-
ing), do not connect the pole terminal of the charger directly to the negative
terminal of the vehicle battery, but rather only to the engine earth » page 220,
Jump-starting using the battery from another vehicle .
Replacing
Read and observe
and on page 200 first.
The new vehicle battery must have the same capacity, voltage, current and
size as the original battery. Suitable vehicle battery types can be purchased
from a specialist garage.
We recommend having the battery replaced by a specialist garage, where the
new vehicle battery will be installed properly and the original battery will be
disposed of in accordance with national regulations.
Disconnecting and reconnecting
Read and observe
and on page 200 first.
Disconnecting
›
Switch off the ignition.
202General Maintenance
Fig. 206
Engine earth: START-STOP sys-
tem
Read and observe on page 220 first.
The starting process using the battery of another vehicle requires the use of
jumper cables.
The jump-start cables must be attached in the following sequence.
›
Attach clamp
1
to the positive terminal of the discharged battery
A
» Fig. 205 .
›
Attach clamp
2
to the positive terminal of the battery supplying power
B
.
›
Attach clamp
3
to the negative terminal of the battery supplying power
B
.
›
Attach the clamp
4
to a solid metal part which is connected firmly to the en-
gine block or to the engine block itself.
On vehicles with the START-STOP system » Fig. 206, connect the jump-start
cable to the engine's earthing point.
Starting engine
›
Start the engine on the vehicle providing the power and allow it to idle.
›
Start the engine of the vehicle with the discharged battery.
›
If the engine does not start, terminate the attempt to start the engine after
10 seconds and wait for 30 seconds before repeating the process.
›
Remove the jump-start cables exactly in the reverse sequence as for attach-
ing.
Both batteries must have a rated voltage of 12 V. The capacity (Ah) of the bat-
tery supplying the power must not be significantly less than the capacity of
the discharged battery in your vehicle.
Jump-start cables
Only use jump-start cables which have an adequately large cross-section and
insulated terminal clamps. Observe the instructions of the jumper lead manu-
facturer.
Positive cable – colour coding in the majority of cases is red.
Negative cable – colour coding in the majority of cases is black.WARNING■
Do not clamp the jump-start cable to the negative terminal of the dis-
charged battery. There is the risk of detonating gas seeping out the battery being ignited by the strong spark which results from the engine being star-
ted.■
The non-insulated parts of the terminal clamps must never touch each
other – risk of short circuit!
■
The jump-start cable connected to the positive terminal of the battery
must not come into contact with electrically conducting parts of the vehicle
– risk of short circuit!
■
Route the jump-start cables so that they cannot be caught by any rotat-
ing parts in the engine compartment.
■
There must not be any contact between the two vehicles otherwise cur-
rent may flow as soon as the negative terminals are connected.
Towing the vehicle
Introduction
Fig. 207
Braided tow ropes/spiral tow rope
This chapter contains information on the following subjects:
Front towing eye
222
Rear towing eye
223
Vehicles with a tow hitch
223
A braided tow rope must be used for towing » Fig. 207-
.
When towing, the following guidelines must be observed.
221Emergency equipment, and self-help