Page 311 of 506

309 Operation
Engine compartment
Replace and tighten cap.
For more information on coolant, see the 
“Technical data” section (
page 466).
Battery
Your vehicle is equipped with two batter-
ies:
Auxiliary battery (located in the engine 
compartment).
Main battery (starter and electrical 
consumers; located in the trunk).
These batteries should always be suffi-
ciently charged in order to achieve their 
rated service life. Refer to Maintenance 
Booklet for battery maintenance intervals.
If you use your vehicle mostly for short-dis-
tance trips, you will need to have the bat-
tery charge checked more frequently.When replacing batteries, always use bat-
teries approved by Mercedes-Benz. 
If you do not intend to operate your vehicle 
for an extended period of time, consult an 
authorized Mercedes-Benz Center about 
steps you need to observe.
Batteries contain materials that can harm 
the environment if disposed of improperly. 
Recycling of batteries is the preferred 
method of disposal. Many states require 
sellers of batteries to accept old batteries 
for recycling.
G
Observe all safety instructions 
and precautions when handling 
automotive batteries. 
A
Risk of explosion.
D
Keep flames or sparks away 
from battery. Do not smoke.
B
Battery acid is caustic. Do not 
allow it to come into contact 
with skin, eyes or clothing. 
In case it does, immediately 
flush affected area with clear 
water and seek medical help if 
necessary.
E
Wear eye protection.
C
Keep children away.
F
Follow the instructions in this 
Operator's Manual. 
     
        
        Page 435 of 506

433 Practical hints
Batteries
Batteries
Your vehicle is equipped with two batter-
ies:
Main battery (battery for starter and 
electrical consumers; located in the 
trunk).
Auxiliary battery (back-up battery; sta-
bilizes the electrical system if the main 
battery is discharged; located in the en-
gine compartment)
The main battery is in the trunk under the 
luggage box. Remove the luggage box 
(
page 408).
Vehicles with spare wheel1Negative terminal
2Positive terminalWarning!
G
Jump starting must only be done using the 
main battery in the trunk.
Warning!
G
Failure to follow these instructions can re-
sult in severe injury or death.
Observe all safety instructions and precau-
tions when handling automotive batteries 
(page 309).
Never lean over batteries while connecting, 
you might get injured.
Battery fluid contains sulfuric acid. Do not 
allow this fluid to come in contact with eyes, 
skin or clothing. In case it does, immediately 
flush affected area with water and seek 
medical help if necessary.
A battery will also produce hydrogen gas, 
which is flammable and explosive. Keep 
flames or sparks away from battery, avoid 
improper connection of jumper cables, 
smoking etc. 
     
        
        Page 460 of 506
458 Technical dataElectrical systemModel
E320, E3204MATIC
E 500, E 500 4MATIC
E55AMG
Generator (alternator)
14 V/150 A
14 V/150 A
14 V/180 A
Starter motor
14 V/1.4 kW
14 V/1.7 kW
14 V/1.7 kW
Battery (auxiliary)
12 V/12 Ah
12 V/12 Ah
12 V/12 Ah
Battery (main)
12 V/95 Ah
12 V/95 Ah
12 V/95 Ah
Spark plugs
Bosch F8 DPP 332U
NGK PFR 5R-11
Bosch F8 DPP 332U
NGK PFR 5R-11
NGK IL FR 6 A
Electrode gap
0.039 in (1.00 mm)
0.039 in (1.00 mm)
0.031 in (0.8 mm)
Tightening torque
18.5 - 22 lb-ft (25 - 30 Nm)
18.5 - 22 lb-ft (25 - 30 Nm)
18.5 - 22 lb-ft (25 - 30 Nm)
Model
E 320 CDI
Generator (alternator)
14 V/200 A
Starter motor
14 V/2.2 kW
Battery (auxiliary)
12 V/12 Ah
Battery (main)
12 V/95 Ah