Page 427 of 521

426 Practical hints
Where will I find...?
In case of a flat tire, you may temporarily
use the Minispare wheel when observing
the following restrictions:
Do not exceed a vehicle speed of
50 mph (80 km/h).
Drive to the nearest tire repair facility
to have the flat tire repaired or
replaced as appropriate.
Do not operate vehicle with more than
one Minispare wheel mounted.
For more information, see “Rims and tires”
(
page 482).
Spare wheel bolts
The spare wheel bolts are fixed at the
Minispare wheel.
1Wheel bolt for light alloy rims
2Wheel bolt for Minispare wheel
(located in trunk with spare wheel)
!To prevent damage, always disengage trunk
floor handle from upper edge of trunk and lower
trunk floor before closing the trunk.
Warning!G
The dimensions of the Minispare wheel are
different from those of the road wheels. As
a result, the vehicle handling characteristics
change when driving with a Minispare wheel
mounted.
The Minispare wheel should only be used
temporarily, and should be replaced with a
regular road wheel as quickly as possible.
Do not switch off the ESP
® when a Minis-
pare wheel is mounted.
!Wheel bolts2 must be used when mount-
ing the Minispare wheel. The use of any wheel
bolts other than wheel bolts2 for the Minispare
wheel will physically damage the vehicle’s
brakes.
Warning!G
Make sure to use the original length wheel
bolts when remounting the original wheel
after it has been repaired.
Page 428 of 521

427 Practical hints
Unlocking/locking in an emergency
Unlocking/locking in an emergency
Unlocking the vehicle
If you are unable to unlock the vehicle with
the SmartKey or KEYLESS-GO*, open the
driver’s door and the trunk using the
mechanical key.
1Mechanical key locking tab
2Mechanical key
Move locking tab1 in the direction of
arrow.
Slide mechanical key2 out of the
housing.Unlocking the driver’s doorInsert the mechanical key2 into the
driver’s door lock until it stops.
Turn the mechanical key2 counter-
clockwise to position1 until the lock-
ing knob moves up.
The driver’s door is unlocked.
Pull the door handle to open the
driver’s door.
iUnlocking and opening the driver’s door
and/or the trunk with the mechanical key will
trigger the anti-theft alarm system.
To cancel the alarm, do one of the following:
Press button Œ or ‹on the
SmartKey.
Insert the SmartKey in the starter switch.
Vehicles with KEYLESS-GO*:
Pull the outside door handle.
Press the KEYLESS-GO* start/stop button
(
page 39).
1Unlocking
2Mechanical key
Page 429 of 521

428 Practical hints
Unlocking/locking in an emergency
Unlocking the trunk
A minimum height clearance of 5.71 ft
(1.74 m) (CLK coupe) or 5.41 ft (1.65 m)
(CLK cabriolet) is required to open the
trunk lid.
The trunk lid lock is located next to the
handle above the rear license plate recess.Insert the mechanical key3 into the
trunk lid lock until it stops.
Turn the mechanical key3
counterclockwise to position1 and
hold it in this position.
Pull the trunk lid handle2 and lift the
trunk lid.
The trunk opens.
Turn the mechanical key3 back and
remove it from the trunk lid lock.
Locking the vehicle
If you cannot lock the vehicle with the
SmartKey or SmartKey with
KEYLESS-GO*, do the following:
Close the passenger door and the
trunk.
Press the central locking switch in the
center console (
page 118).
Check to see whether the locking knob
on the passenger door has moved
down.
If necessary, push it down manually.
Remove the mechanical key out of the
SmartKey (
page 427).
Check whether the trunk is locked.
If necessary, lock the trunk with the
mechanical key (
page 118).
Except for the driver’s door, the vehicle
should now be locked.
1Unlocking in an emergency
2Handle
3Mechanical key
!The trunk lid swings open upwards
automatically. Always make sure there is suffi-
cient overhead clearance.
Page 431 of 521

430 Practical hints
Opening/closing in an emergency (Cabriolet)
Operating roll bars manually
Releasing roll bars manually
If the roll bar system is malfunctioning, you
can release the roll bars manually.Close the soft top (page 261).
Open the trunk (page 110).
Fold back the luggage cover
(
page 264).
Take hex wrench out of its storage
location in the storage well casing
(
page 422).
1Perforation
Push hex wrench through
perforation1 in trim of rear wall in
trunk.
2Hex wrench
Warning!G
If the yellow roll bar warning lamp in
the clock does not go out after starting the
engine, or if it comes on while driving, then
the roll bar system is not operating properly
and may not activate in an accident. In this
case, raise the roll bars manually before
continuing to drive.
For safety reasons drive only with the roll
bars raised until the malfunction is repaired.
Have your vehicle checked at an authorized
Mercedes-Benz Center.
iWith the roll bars released, the soft top can-
not be operated using the soft top switch and the
rear head restraints cannot be lowered using the
rear head restraint lowering switch.
Warning!G
Make sure no one is located in the roll bar’s
path of motion while the next steps are be-
ing carried out.
When the roll bar is manually released, the
rear head restraints and the roll bar under-
neath shoot up almost instantaneously.
Page 432 of 521

431 Practical hints
Opening/closing in an emergency (Cabriolet)
Insert long side of hex wrench2 into
opening.
Using hex wrench 2, press release
catch down in direction of arrow.
The roll bar extends with a loud sound.
Repeat this step for the second roll bar.
Have the systems checked at an autho-
rized Mercedes-Benz Center as soon as
possible.
Lowering roll bars manually
With the soft top open, you can lower the
roll bars manually after they have been re-
leased.
1Orientation seam
2Hex wrench
3Press wrench down
4Press head restraint down
Take hex wrench out of its storage
location in the storage well casing
(
page 422).
Align hex wrench so that its long side is
parallel to orientation seam1 and in-
sert hex wrench2 into gap on left side
of respective head restraint.
Press hex wrench down firmly in direc-
tion of arrow3 and hold.
Press head restraint down in direction
of arrow4.
Pull hex wrench 2 out and take weight
off head restraint.
Repeat this procedure on roll bar for
second head restraint.
iWith the roll bars released, the soft top can-
not be operated using the soft top switch and the
rear head restraints cannot be lowered using the
rear head restraint lowering switch.
Warning!G
Never lower the roll bars manually unless
the soft top is open. Otherwise, the roll bars
function could be impaired, no longer reduc-
ing your risk of injury in an optimal manner.
Contact an authorized Mercedes-Benz Cen-
ter to have the roll bar lowered when the
soft top is closed.
Page 433 of 521

432 Practical hints
Opening/closing in an emergency (Cabriolet)
Soft top emergency operation
If the soft top cannot be automatically
closed, check the following:
Is the luggage cover engaged in place
(
page 264)?
Have the roll bars been released? If so,
lower the roll bars manually
(
page 431).
Is the trunk lid closed (page 112)?
Is there sufficient on-board voltage?
Start the engine if necessary.
These messages will also appear in the
multifunction display (
page 420).
If automatic operation still does not func-
tion properly, you can close the soft top
manually.
This procedure should be performed with
great care by two persons.
Engage parking brake.
Lower the side windows.
Lower rear head restraints
(
page 123).
For safety reasons, remove SmartKey
from starter switch.
Open the trunk.
Remove the trunk floor cover.
Take the two straps for soft top emer-
gency operation out of vehicle tool kit
(
page 422).
Take hex wrench out of its storage
location in the storage well casing
(
page 422).
Open the left side trim panel in the
trunk.
!Manually closing the soft top is a complicat-
ed and technically demanding procedure. Close
the soft top manually in emergency cases only.
Otherwise, visit an authorized Mercedes-Benz
Center. Please read the instructions fully before
beginning operation and only undertake it with
another person and if you feel fully capable of
performing the tasks involved.
Warning!G
It is important that a second person
helps you. Otherwise, you could become
trapped or injured.
Remove any wristwatches or jewelry
such as rings or bracelets. Otherwise,
they could get caught in the vehicle
mechanism, causing personal injury to
yourself or damage to the vehicle.
Always use the grips provided as indi-
cated. Otherwise you could injure your-
self.
iIf the rear head restraints cannot be lowered
using the rear head restraint lowering switch, the
roll bars may have been released. For more infor-
mation, see “Operating roll bars manually”
(
page 430).
Page 441 of 521

440 Practical hints
Resetting activated head restraints
Resetting activated head restraints
If the active head restraints have been trig-
gered in a rear-end collision, the active
head restraints must be reset. Otherwise,
the active head restraints cannot offer any
additional protection in the event of anoth-
er rear-end collision.
You can tell that the head restraints have
been triggered when they have been
moved forward and cannot be adjusted.
1Reset tool
2Hole
3Press head restraint cushion
Take the reset tool1 out of the
Mercedes-Benz vehicle literature
pouch.
Guide reset tool1 into the hole2 be-
tween the rear head restraint cover and
the head restraint cushion.
Press the reset tool1 downward until
you hear the active head restraint re-
lease mechanism audibly engage.
Pull out reset tool1.
Firmly press the head restraint cushion
back in direction of arrow3 toward
the rear head restraint cover until it
engages.
Repeat this procedure on the active
head restraint for the second front
seat.
After resetting the active head re-
straints store the reset tool1 in the
Mercedes-Benz vehicle literature
pouch.
For information on active head restraints,
see “Active head restraints” (
page 81).
For information on head restraint adjust-
ment, see “Seats” (
page 41).
iFor your convenience, we recommend that
you have this work carried out at an authorized
Mercedes-Benz Center.
You will find the reset tool for manually operating
the active head restraints in the Mercedes-Benz
vehicle literature pouch.
Warning!G
For safety reasons, have the active head re-
straints checked at an authorized
Mercedes-Benz Center after a rear-end
collision.
Warning!G
When pushing back the head restraint cush-
ion, take care that your fingers do not be-
come caught between the head restraint
cushion and the cover. Failing to do so may
lead to injury.!Be careful not to damage upholstery.
Page 443 of 521
442 Practical hints
Replacing SmartKey batteries
SmartKey / SmartKey with
KEYLESS-GO*
Replacement batteries: Lithium, type
CR 2025 or equivalent.
Remove the mechanical key from the
SmartKey or SmartKey with
KEYLESS-GO* (
page 427).
1Mechanical key
2Battery compartment
Insert mechanical key1 into the
opening.
Press mechanical key1 in direction of
arrow.
The battery compartment2 is un-
latched.
Pull battery compartment2 out of the
housing.
3Batteries
4Contact spring
Remove the batteries3.
Using a lint-free cloth, insert new
batteries3 under the contact
springs4 with the positive terminal
(+) side facing up.
Return battery compartment2 into
housing until it locks into place.
Slide mechanical key 1 back into the
SmartKey.
Check the operation of the SmartKey.