Checking the battery electrolyte levelFig. 150
Vehicle battery: Electrolyte level
indicator
Read and observe and on page 147 first.
On vehicles with a vehicle battery fitted with a colour indicator, the electrolyte
level can be determined by looking at the change in colour of this display.
Air bubbles can influence the colour of the indicator. For this reason carefully
knock on the indicator before carrying out the check.
Check
Black colour – electrolyte level is correct.
Colourless or light yellow colour – electrolyte level too low, the battery must
be replaced.
For technical reasons, on vehicles with the description “AGM”, the electrolyte
level cannot be checked.
Vehicles with the START-STOPsystem are fitted with a battery control unit for
checking the energy level for recurring engine starts.
We recommend that you have the acid level checked regularly by a specialist
garage, especially in the following cases. ▶ High external temperatures.
▶ Longer day trips.
▶ After each charge.
Winter time
The vehicle battery only has a proportion of the starting power in lower tem- peratures. A discharged vehicle battery may already freeze at temperatures
just below 0 °C .
We therefore recommend that you have the battery checked and, if necessary,
recharged by a specialist garage before the start of the winter.
NoteThe battery acid level is also checked regularly by a specialist garage as part of
the inspection service.
Charging
Read and observe
and on page 147 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 “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.
148General Maintenance
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 consumers 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, the pole terminal of the charger
must not be connected directly to the negative terminal of the vehicle battery,
but only to the engine earth » page 164, Jump-starting using the battery from
another vehicle .
Replacing
Read and observe
and on page 147 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 you have the battery replaced by a specialist garage.
Disconnecting and reconnecting
Read and observe
and on page 147 first.
Disconnecting
›
Switch off the ignition.
›
First, disconnect the negative terminal
first, then the positive
terminal
of the battery.
Connecting›First, connect the positive first, then the negative battery terminal.
After disconnecting and re-connecting the vehicle battery, the following func-
tions or devices are partially or completely inoperative.Function / deviceCommissioningTime settings» page 31
CAUTION
■ Disconnect the vehicle battery only with the ignition turned off - there is a
risk of damaging the electrical system of the vehicle.■
Under no circumstances must the battery cables be connected incorrectly –
risk of a cable fire.
Note
■ After disconnecting and re-connecting the vehicle battery, we recommend
having the vehicle checked by a specialist to ensure that the full functionality
of all electrical systems is guaranteed.■
The data of the multi-function display will be reset.
Automatic load deactivation
Read and observe
and on page 147 first.
The vehicle's electrical system automatically prevents the battery from dis-
charging when the battery is being heavily used. This manifests itself by the
following. ▶ The idling speed is raised to allow the generator to deliver more electricity to
the electrical system.
▶ Where necessary, large convenience consumers such as seat heaters and
rear window heaters have their power limited or are shut off completely in
the event of an emergency.
CAUTION
■ Despite such intervention by the vehicle electric system management, the
vehicle battery may be drained. For example, when the ignition is switched on
a long time with the engine turned off or the side or parking lights are turned
on during longer parking.■
Consumers that are supplied via a 12-V power socket can cause the vehicle
battery to discharge when the ignition is switched off.
149Inspecting and replenishing
The jump-start cable must be connected to the engine earthing point C» Fig. 164 only on vehicles with the START-STOP system.
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, halt the attempt to start the engine after 10 sec-
onds and wait for 30 seconds before repeating the process.
›
Remove the jump start cables in the reverse order as attachment.
Engines in vehicles with the vehicle battery in the boot
The positive terminal
A
is located under a cover in the engine compartment
» Fig. 165 .
›
Unlock the retainer tab on the cover in direction of arrow
1
.
›
Open the cover in the direction of the arrow
2
.
›
Clamp the positive terminal of the jumper cable to the position
A
» Fig. 165 .
›
Clamp the negative terminal of the jumper cable to the earthing point of the
engine
D
» Fig. 164 or on a metal part firmly connected to the engine block
or directly on the engine block.
›
Remove the jump start cables in the reverse order as attachment.
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 – there is a risk of short circuit.
WARNING (Continued)■ The jump-start cable connected to the positive terminal of the battery
must not come into contact with electrically conducting parts of the vehicle
– there is a risk of short circuit.■
Route the jump-start cables so that they cannot be caught by any rotat-
ing parts in the engine compartment.
Towing the vehicle
Introduction
Fig. 166
Braided tow rope / Spiral tow rope
This chapter contains information on the following subjects:
Front towing eye
166
Rear towing eye
167
Vehicles with a tow hitch
167
For towing a braided tow rope is to be used » Fig. 166-
.
When towing, the following guidelines must be observed.
Vehicles with manual transmission may be towed in with a tow bar or a tow
rope or with the front or rear wheels raised.
Vehicles with automatic transmission may be towed in with a tow bar or a tow
rope or with the front wheels raised. If the vehicle is raised at the rear, the au-
tomatic gearbox will be damaged! If possible, the vehicle should be towed with
the engine running or at least with the ignition on.
Driver of the tow vehicle
›
Engage the clutch gently when starting off or depress the accelerator partic-
ularly gently if the vehicle is fitted with an automatic gearbox.
165Emergency equipment and self-help
I
Ice scrapers
132
Ignition lock92
Immobilizer91
Indicator lights31
Individual settings Locking
52
Unlocking52
Inertia reels13
Information system39
Compass point display45
Door warning39
Gear recommendation39
MAXI DOT display42
Multifunction display40
operation40
Service interval display46
Information system operation40
Infotainment4
Instrument cluster28
Auto-check control39
Counter for distance driven30
Display29
Fuel gauge30
Indicator lights31
Overview28
Revolution counter29
see instrument cluster28
Temperature gauge29
Interior care134
Natural leather134
interior light Front
63
Interior monitor54
iPad holder Behind the headrests
80
Handling79
ISOFIX22
J
Jack
157
Maintenance133
Jacking points Raise vehicle
160
Jump-starting164
K
KESSY Locking
51
Unlocking51
Key Lock
50
Start the engine92
Stopping the engine92
Switch off the ignition92
Switch on the ignition92
Unlock50
L
Lamp failure Warning light
37
Lamps Warning light
37
Leather Natural leather care
134
LEAVING HOME
62
Lever Main beam
60
Turn signal60
Windscreen wipers66
Light COMING HOME / LEAVING HOME
62
Daytime running lights60
Fog Lights61
Headlights with CORNER function62
Parking light63
Rear fog light61
Lighting Luggage compartment80
Lights59
Automatic driving lamp control61
Beam range adjustment59
Cockpit63
Hazard warning light system62
Headlight flasher60
Indicator lights31
Low beam59
Main beam60
Parking light59
Replacing bulbs173
switching on/off59
Turn signal60
Load180
Lock Key
50
Locking Individual settings
52
KESSY51
Remote control50
Locking and unlocking the vehicle from the in- side
51
Locking the door without a locking cylinder Emergency
168
Low beam59
Low tyre pressure warning refer to the tyre pressure monitoring
115
Luggage compartment80
Cover83
Fastening elements81
Fixing nets82
floor covering on both sides84
Lighting80
unlock manually168
Unlock the boot lid168
Luggage compartment cover83
Luggage compartment lid55
191Index
SmartGateConnection by searching for a Wi-Fi network47
introductory information47
Password/PIN code change48
Setting48
Wi-Fi Direct48
SmartLink see Infotainment
4
Snow chains155
Spare wheel153
Remove158
stow158
Speed control system110
Speed symbol See Wheels
154
Spoiler128
Stabilisation system105
Stability Control (ESC)106
Staring engine Jump-starting
164
START-STOP95
Jump-starting164
Manually deactivating/activating the system97
operation96
Warning light38
START-STOP system95
Starter button Problems with the engine start
95
Steering column lock locking93
Steering column lock unlocking93
Switching off the engine94
Switch off the ignition94
Switch on the ignition94
Starting and stopping the engine at the push of the button
93
Starting and stopping the engine using the key 91
Starting engine Jump-starting
164
Starting the engine Starter button
94
START STOPInformation messages97
Start the engine Key
92
Steering column lock locking Starter button
93
Steering column lock unlocking Starter button
93
Steering lock locking Key
92
Steering lock unlocking Key
92
Steering wheel correct posture
9
setting9
Stop see Parking
99
Stopping the engine Key
92
Storage72
Storage compartment Glasses compartment
77
in the boot84
in the centre console73
in the front arm rest77
on the front passenger side77
Storage compartments72
Stowage compartments in the doors
73
Sun visors65
Switching off the engine Starter button
94
Switch light on/off59
Switch off the ignition Key
92
Starter button94
Switch on the ignition Key
92
Starter button94
T
Tablet holder Behind the headrests
80
Taking care of your vehicle Automatic car wash system
130
High-pressure cleaner130
Washing by hand129
Wash system130
TCS Operation
106
Warning light33
Technical data179
Time31
Tiptronic101
Tools157
TOP TETHER24
Towing165
Towing a trailer124
Towing device Accessories
122
Description118
Operation and maintenance133
Towing eye Front
166
Rear167
Towing protection54
Towing the vehicle165
Traction control (TCS)106
Trailer122
13-pin socket123
connection and disconnection123
Load124
Loading123
Safety eye123
Towing a trailer124
Trailer operation117
Trailer stabilization system (TSA)107
Transmission Warning messages
36
194Index