333 Practical hints
Unlocking/locking in an emergency
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
1Mechanical key
2Battery compartment
Replacement batteries: Lithium, type
CR 2025 or equivalent.
Remove mechanical key1
(page 331).
Insert the mechanical key1 in side
opening and push gray slide.
The battery compartment is unlatched.
Pull the battery compartment2 out of
the SmartKey housing in direction of
arrow.
Remove the batteries.3Battery
4Contact spring
Using a lint-free cloth, insert new
batteries3 under the contact
spring4 with the plus (+) side facing
up.
Return battery compartment into hous-
ing until it locks into place.
iWhen changing batteries, always re-
place both batteries.
The required replacement batteries are
available at any authorized
Mercedes-Benz Center.
334 Practical hintsUnlocking/locking in an emergencySmartKey with KEYLESS-GO*
1Battery
2Tilt battery up
3Mechanical keyReplacement battery: Lithium, type
CR 2025 or equivalent.
Remove mechanical key (
page 331).
Insert the mechanical key in side open-
ing and push gray slide.
The battery compartment is unlatched.
Pull the battery compartment out of the
SmartKey housing.
Using mechanical key3, apply pres-
sure to position2.
Battery1 tilts up slightly.
Pull out battery1 in direction of ar-
row.
Using a lint-free cloth, insert new bat-
tery with the plus (+) side facing up.
Return battery compartment into hous-
ing until it locks into place.
Fuel filler flap
In case the central locking system does
not release the fuel filler flap, you can it
manually.
1Release knob
Open the trunk.
Remove the battery cover and the trim
inside the trunk on the right-hand side.
Pull release knob 1 in the direction of
arrow.
The fuel filler flap can be opened.
iThe required replacement battery is
available at any authorized
Mercedes-Benz Center.
