Page 365 of 464

365 Practical hints
What to do if …
.
Low beam, left
The left low beam lamp is malfunc-
tioning.
Halogen headlamp:
Replace the bulb as soon as possible.
Bi-Xenon* headlamp:
Visit an authorized Mercedes-Benz Center 
as soon as possible.
Low beam, right
The right low beam lamp is malfunc-
tioning.
Halogen headlamp:
Replace the bulb as soon as possible.
Bi-Xenon* headlamp:
Visit an authorized Mercedes-Benz Center 
as soon as possible.
Park. light,
front left
The left front parking lamp is mal-
functioning.
Replace the bulb as soon as possible.
Park. light,
front right
The right front parking lamp is mal-
functioning.
Replace the bulb as soon as possible.
Remove key
You have forgotten to remove the 
SmartKey.
Remove the SmartKey from the starter 
switch.
Side marker lamp,
front left
The left front side marker lamp is 
malfunctioning.
Replace the bulb as soon as possible.
Side marker lamp,
front right
The right front side marker lamp is 
malfunctioning.
Replace the bulb as soon as possible.
Display symbol
Display message
Possible cause
Possible solution 
     
        
        Page 366 of 464

366 Practical hintsWhat to do if ….
Rear left side marker
lamp malfunction
The left rear side marker lamp is 
malfunctioning. This message will 
only appear if a critical number of 
LEDs have stopped working.
Visit an authorized Mercedes-Benz Center 
as soon as possible.
Rear right side marker
lamp malfunction
The right rear side marker lamp is 
malfunctioning. This message will 
only appear if a critical number of 
LEDs have stopped working.
Visit an authorized Mercedes-Benz Center 
as soon as possible.
Tail light, left
Back-up lamp on
The left tail lamp is malfunctioning. 
This message will only appear if a 
critical number of LEDs have 
stopped working. A backup bulb 
has been brought into use.
Visit an authorized Mercedes-Benz Center 
as soon as possible.
Tail light, right
Back-up lamp on
The right tail lamp is malfunction-
ing. This message will only appear if 
a critical number of LEDs have 
stopped working. A backup bulb 
has been brought into use.
Visit an authorized Mercedes-Benz Center 
as soon as possible.
Turn off
lights
You have forgotten to switch off the 
headlamps when exiting the vehicle 
and no SmartKey is in the starter 
switch.
Switch off the headlamps.
Display symbol
Display message
Possible cause
Possible solution 
     
        
        Page 380 of 464
380 Practical hintsReplacing bulbsSafe vehicle operation depends on proper 
exterior lighting and signaling. It is there-
fore essential that all bulbs and lamp as-
semblies are in good working order at all 
times.
Correct headlamp adjustment is extremely 
important. Have headlamps checked and 
readjusted at regular intervals and when a 
bulb has been replaced. See an authorized 
Mercedes-Benz Center for headlamp ad-
justment.
Bulbs
iIf the headlamps are fogged up on the 
inside as a result of high humidity, 
driving the vehicle a short distance with 
the lights on should clear up the 
fogging.iBackup bulbs will be brought into use 
when lamps malfunction. Observe the 
messages in the multifunction display 
(page 363). 
     
        
        Page 381 of 464

381 Practical hints
Replacing bulbs
Front lamps Rear lamps
Lamp
Type
1
Additional turn signal 
lamp
LED
2
Turn signal lamp
PY 21 W
3
Halogen headlamp:
Low beam
Bi-Xenon* headlamp:
Low and high beam
1
1Vehicles with Bi-Xenon* headlamps: Low beam
and high beam use the same D2S-35W lamp. Do
not replace the Bi-Xenon* bulbs yourself. See an
authorized Mercedes-Benz Center.
H7 (55 W)
D2S-35W
4
Front fog lamp
HB4 (51 W)
 5
Parking and standing 
lamp
W5W
6
Halogen headlamp:
High beam/high beam 
flasher
Bi-Xenon* headlamp:
High beam flasher
H7 (55 W)
H7 (55 W)
7
Side marker lamp
W5W
Lamp
Type
8
Rear fog lamp (driver’s 
side only)
P21W
9
High mounted brake 
lamp
LED
a
Tail, parking, standing, 
side marker lamp and 
brake lamp
LED
b
License plate lamps
C5W
c
Backup lamp
P21W
d
Turn signal lamp
P21W
iVehicles equipped with cornering fog 
lamps*:
Front fog lamps use H7 (55 W) lamps.
Warning!
G
Bulbs and bulb sockets can be very hot. Al-
low the lamp to cool down before changing 
a bulb.
Keep bulbs out of reach of children.
Halogen lamps contain pressurized gas. 
A bulb can explode if you:
touch or move it when hot
drop the bulb
scratch the bulb
Wear eye and hand protection.
Because of high voltage in Xenon lamps, it is 
dangerous to replace the bulb or repair the 
lamp and its components. We recommend 
that you have such work done by a qualified 
technician. 
     
        
        Page 382 of 464
382 Practical hintsReplacing bulbsNotes on bulb replacement
Only use 12-volt bulbs of the same type 
and with the specified watt rating.
Switch lights off before changing a bulb 
to prevent short circuits.
Always use a clean lint-free cloth when 
handling bulbs.
Your hands should be dry and free of oil 
and grease.
If the newly installed bulb does not 
come on, visit an authorized 
Mercedes-Benz Center.Have the LEDs and bulbs for the following 
lamps replaced by an authorized 
Mercedes-Benz Center:
Additional turn signal lamps in the 
exterior rear view mirrors
Bi-Xenon* lamps
Front fog lamps
High mounted brake lamp
Brake lamps
Front and rear side marker lamps
Parking/standing lamps in the tail 
lamp assemblies
Replacing bulbs for front lamps
Before you start to replace a bulb for a 
front lamp, do the following first:
Turn the exterior lamp switch to 
positionM (
page 106).
Open the hood (
page 287) (except 
for side marker lamps).
iHave the headlamp adjustment 
checked regularly. 
     
        
        Page 383 of 464
383 Practical hints
Replacing bulbs
1Housing cover for low beam (halogen 
headlamps only)
Housing cover for Bi-Xenon* head-
lamps. Do not remove.
2Bulb socket for turn signal lamp
3Bulb socket for high beam/high beam 
flasher lamp
4Bulb socket for parking and standing 
light lamp
5Bulb socket for low beam bulb (Halo-
gen headlamps only)Low beam bulb (Halogen headlamps 
only)
Turn housing cover1 counterclock-
wise and remove.
Turn bulb socket5 with the bulb 
counterclockwise and remove.
Pull the bulb out of bulb socket5.
Press the new bulb into bulb socket5.
Place bulb socket5 back into the 
lamp and turn it clockwise.
Reinstall housing cover1.
Warning!
G
Do not remove the cover1 for the Bi-Xe-
non* headlamp. Because of high voltage in 
Bi-Xenon lamps, it is dangerous to replace 
the bulb or repair the lamp and its compo-
nents. We recommend that you have such 
work done by a qualified technician. 
     
        
        Page 384 of 464

384 Practical hintsReplacing bulbsHigh beam/high beam flasher bulb 
(Halogen headlamps) / High beam 
flasher bulb (Bi-Xenon* headlamps)
Turn bulb socket3 with the bulb 
counterclockwise and remove.
Pull the bulb out of bulb socket3.
Press the new bulb into bulb socket3.
Place bulb socket3 back into the 
lamp and turn it clockwise.Front turn signal bulb
Turn bulb socket2 with the bulb 
counterclockwise and remove.
Press gently onto the bulb and turn it 
counterclockwise out of bulb 
socket2.
Press the new bulb gently into bulb 
socket2 and turn it clockwise.
Place bulb socket2 back into the 
lamp and turn it clockwise.
Parking and standing lamp bulb
Turn bulb socket4 with the bulb 
counterclockwise and remove.
Pull the bulb out of bulb socket4.
Press the new bulb into bulb socket4.
Place bulb socket4 back into the 
lamp and turn it clockwise.
Replacing bulbs for rear lamps
Before you start to replace a bulb for a rear 
lamp, do the following first:
Turn the exterior lamp switch to 
positionM (
page 106).
Open the trunk lid (
page 95).
Tail lamp unit
1Bulb socket for rear fog lamp (driver’s 
side only)
2Bulb socket for turn signal lamp
3Bulb socket for backup lamp 
     
        
        Page 423 of 464
423 Technical data
Fuels, coolants, lubricants, etc.
Model
Capacity
Fuels, coolants, lubricants etc.
Fuel tank
including a reserve of
SLK 350
SLK 55 AMG
approx. 18.5 US gal (70.0 l)
approx. 2.4 US gal (9.0 l)
approx. 18.5 US gal (70.0 l)
approx. 2.6 US gal (10.0 l)
Premium unleaded gasoline:
Minimum posted Octane 91 (average of 
96 RON / 86 MON)
Air conditioning system
R-134a refrigerant and special PAG lubricant oil 
(never R-12)
Hydraulic system for 
retractable hardtop
0.19 US qt (0.18 l)
MB Hydraulic Fluid
Windshield washer 
system and headlamp 
cleaning system*
7.4 US qt (7.0 l)
MB Windshield washer concentrate
1
1Use MB Windshield Washer Concentrate“S” and water for temperatures above freezing point or MB Windshield Washer Concentrate “S” and commercially available
premixed windshield washer solvent/antifreeze for temperatures below freezing point. Follow suggested mixing ratios (page 429).