176 Controls in detailClimate controlThe climate control is operational when-
ever the engine is running. You can oper-
ate the climate control system in either the 
automatic or manual mode. The system 
cools or heats the interior depending on 
the selected interior temperature and the 
current outside temperature.Nearly all dust particles, pollutants and 
odors are filtered out before outside air en-
ters the passenger compartment through 
the air distribution system.
The air conditioning will not engage (no 
cooling) if the modeAC
OFF
 is selected 
(
page 181).
Warning!
G
When operating the climate control, the air 
that enters the passenger compartment 
through the air vents in the footwell can be 
very hot or very cold (depending on the set 
temperature). This may cause burns or frost-
bite on unprotected skin in the immediate 
area of the air vents. Always keep sufficient 
distance between unprotected parts of the 
body and the footwell air vents. If necessary, 
change the air flow using the air distribution 
controls to direct the air away from the foot-
well air vents (
page 178).
Warning!
G
Follow the recommended settings for heat-
ing and cooling given on the following pag-
es. Otherwise the windows could fog up, 
impairing visibility and endangering you and 
others.
iSevere conditions (e.g. strong air 
pollution) may require replacement of 
the filter before its scheduled interval. 
A clogged filter will reduce the air 
volume to the interior.
If the vehicle interior is hot, ventilate 
the interior before driving off, see 
“Opening (Summer opening feature)” 
(page 229).
Keep the air intake grille in front of the 
windshield free of snow and debris.
Do not obstruct air flow by placing 
objects on the air flow-through exhaust 
slots below the rear window. 
390 Technical dataFuels, coolants, lubricants, etc.Engine oils
Engine oils are specifically tested for their 
suitability in our engines and durability for 
our service intervals. Therefore, only use 
approved engine oils and oil filters 
required for vehicles with Maintenance 
System (U.S. vehicles) or FSS (Canada 
vehicles). For a listing of approved engine 
oils and oil filters, refer to the Factory 
Approved Service Products pamphlet, or 
contact an authorized Mercedes-Benz 
Center.
Using engine oils and oil filters of 
specification other than those expressly 
required for the Maintenance System 
(U.S. vehicles) or FSS (Canada vehicles), or 
changing of oil and oil filter at change 
intervals longer than those called for by 
the Maintenance System (U.S. vehicles) or 
FSS (Canada Vehicles) will result in engine 
damage not covered by the 
Mercedes-Benz Limited Warranty.Please follow Maintenance System 
(U.S. vehicles) or FSS (Canada vehicles) 
recommendations for scheduled oil 
changes. Failure to do so will result in 
engine damage not covered by the 
Mercedes-Benz Limited Warranty.
Engine oil additives
Do not blend oil additives with engine oil. 
They may damage the engine.
Damage or malfunctions resulting from 
blending oil additives are not covered by 
the Mercedes-Benz Limited Warranty.Air conditioning refrigerant
R-134a (HFC) refrigerant and special PAG 
lubricating oil is used in the air 
conditioning system.
Never use R-12 (CFC) or mineral-based 
lubricating oil. Otherwise damage to the 
system will occur.
Brake fluid
During vehicle operation, the boiling point 
of the brake fluid is continuously reduced 
through the absorption of moisture from 
the atmosphere. Under extremely strenu-
ous operating conditions, this moisture 
content can lead to the formation of 
bubbles in the system, thus reducing the 
system’s efficiency.
Therefore, the brake fluid must be 
replaced every two years, preferably in the 
spring.
Only brake fluid approved by 
Mercedes-Benz is recommended. Your 
authorized Mercedes-Benz Center will 
provide you with additional information.