Disconnecting, removing, charging,
reinstalling and reconnecting 12‑volt
battery
Disconnecting the 12-volt battery i
If the 12-volt battery is disconnected
or discharged
R turning the key in the starter switch
will have no effect
R the transmission will remain in park
position P
For more information see “Jump start-
ing” (Y page 200).
X Engage the parking brake.
X Move the gear selector lever to park
position P.
X Turn off all electrical accessories.
X Switch off the drive system.
X Open the passenger door.
X Move the passenger seat to the rear as far
as possible.
X Unscrew the carpet holder in the
passenger footwell (Y page 160).
X Lift the carpet. X
Unscrew fastening screw ;counter-
clockwise.
X Pull footrest :sideways out of the vehi-
cle.
X Read and observe safety instructions and
precautions (Y page 197). !
Always disconnect the battery in the
order described below. Otherwise the
vehicle’s electronics can be damaged.
X Disconnect the battery negative lead
from negative terminal =.
Make sure the negative lead does not
come into contact with the positive lead.
X Remove cover ?from the positive ter-
minal.
X Disconnect the battery positive lead.
Removing the 12-volt battery X
Unscrew battery mount A.
X Remove the battery support and bracket.
X Pull out the ventilation hose from the
battery.
Depending on battery arrangement in
your vehicle model, the ventilation hose
is located either on the left or right sideof the battery.
X Remove the battery.
Charging the 12-volt battery G
WARNING
Avoid creating sparks when charging the
battery as escaping gases are flammable.
Keep open flames away from the battery and do not smoke.
Do not touch the battery terminal with metal
objects and do not remove the battery
charger’s terminal clamps until the battery charger has been switched off and no fur- Batteries
199>> Practical hints.
Z
No. Accessory/Component Amperage Color
E
CPC, shifter, brake force booster vacuum
pump 7.5 A Brown
F
Coolant pumps 1 and 2, high-voltage battery 15 A Blue
G
ESP
®
control unit 25 A Neutral
H
Exterior lamp switch, turn signal lamp
switch, cockpit switch module, on-board
diagnostics socket, exterior rear view mir-
ror heating, anti-theft warning system,
rain-light sensor, charge level and power
gauges, central locking system, instrument
cluster, Tire Pressure Monitoring System
(TPMS), brake and turn signal lamps (left and right) 10 A Red
I
— — —
J
— — —
K
Safety circuit high-voltage battery 15 A Blue
L
— — —
M
Rear window wiper (coupé only) 15 A Blue
N
ESP
®
control unit, EPS control unit, restraint
systems 10 A Red
O
Electric drive components, engine control
unit, transmission control unit, on-board
diagnostics socket, sound generator 7.5 A Brown
P
Air conditioning system, exterior rear view
mirror adjustment, washer pump, audio, seat
heating, wiper switch, cruise control, soft
top switch (cabriolet only), backup lamp 10 A Red
Q
Auxiliary power outlet 15 A Blue
R
Left low‑beam headlamp 7.5 A Brown
S
Right low‑beam headlamp 7.5 A Brown
T
— — —
U
Right high‑beam headlamp 7.5 A Brown
V
Left high‑beam headlamp 7.5 A Brown
W
Electric drive components 7.5 A Brown Fuses
209>> Practical hints. Z