440 Practical hintsReplacing SmartKey batteriesIf the batteries in the SmartKey/SmartKey
with KEYLESS-GO* are discharged, the ve-
hicle can no longer be locked or unlocked.
It is recommended to have the batteries re-
placed at an authorized Mercedes-Benz
Center.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.SmartKey/SmartKey with
KEYLESS-GO*
Replacement batteries: Lithium, type
CR 2025 or equivalent.
Remove the mechanical key1 out of
the SmartKey/SmartKey with
KEYLESS-GO* (
page 435).
1Mechanical key
2Battery compartment
Insert mechanical key1 into opening.
Press mechanical key1 in direction of
arrow.
The battery compartment is unlatched.
Warning!
G
Batteries contain poisonous and corrosive
substances. Therefore keep the batteries
out of reach of children.
If a battery is swallowed, seek medical help
immediately.
i
When inserting the batteries, make sure
they are clean and free of lint.
i
When replacing batteries, always replace
both batteries.
The required replacement batteries are available
at any Mercedes-Benz Center.
463 Practical hints
Battery
!
The battery is a v
alve-r
egulated l
ead a
cid
(VRLA) battery, also referred to as “fleece” bat-
tery. Such batteries do not require topping-up of
the electrolyte level. VRLA batteries therefore do
not have cell caps and the battery cover is
non-removable. Do not attempt to open the bat-
tery as otherwise the battery will be damaged.
Even though VRLA batteries do not require top-
ping-up of the electrolyte level and cannot be
opened to check the electrolyte level, the bat-
tery condition must be checked periodically by
performing a battery conductance test. Refer to
Maintenance Booklet for battery condition test-
ing intervals.
As with any other battery, disconnect the battery
if you do not intend to operate your vehicle for an
extended period of time to prevent battery dis-
charge or connect an accessory battery charge
unit expressly approved by Mercedes-Benz for
your vehicle model to maintain the battery
charge. Contact an authorized Mercedes-Benz
Center for further information.
!
The factory-equipped VRLA battery is
leak-proofed. Only use a battery as replacement
that has the same security features and is of
identical size, voltage, and capacity as the facto-
ry-equipped battery.
The battery, the battery ventilation hose and the
lateral plug must always be securely installed
when the vehicle is in operation.
!
Never loosen or detach battery terminal
clamps while the engine is running or the Smart-
Key is in the starter switch. Otherwise the alter-
nator and other electronic components could be
severely damaged.
Have the battery checked regularly by an autho-
rized Mercedes-Benz Center.
Refer to Maintenance Booklet for maintenance
intervals or contact an authorized
Mercedes-Benz Center for further information.
Warning!
G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof battery only to avoid the risk
of acid burns in the event of an accident.