328 Practical hintsLocking/unlocking in an emergency
Using the hex-socket wrench provided 
in the vehicle tool kit, carefully turn the 
locking screw 2 approximately one 
quarter turn.
Hook luggage cover into holders 
(page 185).
Let go of the hardtop.
It should gradually lower into the trunk.
When top is completely lowered, return 
locking screw 2 to its original posi-
tion.
Close the lid. 
Replace the trunk floor.
Visit an authorized Mercedes-Benz 
Center as soon as possible.Replacing batteries in the SmartKey/ 
SmartKey with KEYLESS-GO*
If the batteries in the SmartKey or the 
SmartKey with KEYLESS-GO* are dis-
charged, the vehicle can no longer be 
locked or unlocked. It is recommended to 
have the batteries replaced at an autho-
rized 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
1Mechanical key
2Battery compartment
Replacement batteries: Lithium, type 
CR 2025 or equivalent.
!Do not overtighten the screw.
Warning!
G
Keep the batteries out of reach of children.
If a battery is swallowed, seek medical help 
immediately.
iWhen replacing batteries, always re-
place both batteries. The required re-
placement batteries are available at 
any Mercedes-Benz Center.
 
329 Practical hints
Locking/unlocking in an emergency
Remove mechanical key (
page 325).
Insert the mechanical key1in side 
opening and push gray slide.
The battery compartment is unlatched.
Pull battery compartment2out of the 
SmartKey housing in direction of ar-
row.
Remove the batteries.
3Battery
4Contact spring
Using a lint-free cloth, insert new bat-
teries under the contact spring with the 
plus (+) side facing up. 
Return battery compartment into hous-
ing until it locks into place.SmartKey with KEYLESS-GO*
1Battery
2Tilt battery up
3Mechanical key
Replacement batteries: Lithium, type 
CR 2025 or equivalent.
iThe required replacement batteries are 
available at any Mercedes-Benz 
Center.