Engine
Warning/
indicator
lampNSignal type
Possible causes/consequences and M
Solutions
;NThe yellow Check Engine warning lamp lights up while the engine is running.
There may be a malfunction, for example:
Rin the engine management
Rin the fuel injection system
Rin the exhaust system
Rin the ignition system (for vehicles with gasoline engines)
Rin the fuel system
The emission limit values may be exceeded and the engine may be in emergency
mode.
XVisit a qualified specialist workshop immediately.
Vehicles with a diesel engine: the fuel tank has been run dry (
Ypage 166).
XStart the engine three to four times after refueling.
If the yellow Check Engine warning lamp goes out, emergency running mode is
canceled. The vehicle need not be checked.
In some states, you must immediately visit a qualified specialist workshop as soon
as the yellow Check Engine warning lamp lights up. This is due to the legal require-
ments in effect in these states. If in doubt, check whether such legal regulations
apply in the state in which you are currently driving.
8N The yellow reserve fuel warning lamp lights up while the engine is running.
The fuel level has dropped into the reserve range.
XRefuel at the nearest gas station.
8N The yellow reserve fuel warning lamp flashes while the vehicle is in motion.
In addition, the ;Check Engine warning lamp may light up.
The fuel filler cap is not closed correctly or the fuel system is leaking.
XCheck that the fuel filler cap is correctly closed.
XIf the fuel filler cap is not correctly closed: close the fuel filler cap.
XIf the fuel filler cap is closed:visit a qualified specialist workshop.
?NThe red coolant warning lamp lights up while the engine is running and the
coolant temperature gauge is at the start of the scale.
The temperature sensor for the coolant temperature gage is defective.
The coolant temperature is no longer being monitored. There is a risk of engine
damage if the coolant temperature is too high.
XPull over and stop the vehicle safely and switch off the engine, paying attention
to road and traffic conditions. Do not continue driving under any circumstances.
XSecure the vehicle against rolling away (Ypage 178).
XConsult a qualified specialist workshop.
Warning and indicator lamps in the instrument cluster325
On-board computer and displays
Z
You will usually find information about the fuel
grade on the pump. If you cannot find the label
on the pump, ask the staff for assistance.
Information on refueling (
Ypage 163).
Low outside temperatures
iDiesel fuel with improved cold flow proper-
ties is available during the winter months.
Further information about fuel properties can
be obtained from oil companies, e.g. at gas
stations.
Flexible Fuel vehicles
Important safety notes
GWARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and explo-
sion.
You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable, the auxiliary heating before refueling.
GWARNING
Fuel is poisonous and hazardous to health.
There is a risk of injury.
You must make sure that fuel does not come into contact with your skin, eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors. Keep fuel away from children.
If you or others come into contact with fuel,
observe the following:
RWash away fuel from skin immediately
using soap and water.
RIf fuel comes into contact with your eyes,
immediately rinse them thoroughly with
clean water. Seek medical assistance with-
out delay.
RIf fuel is swallowed, seek medical assis-
tance without delay. Do not induce vomit-
ing.
RImmediately change out of clothing which
has come into contact with fuel. Flexible Fuel vehicles can be refueled with the
following fuel types:
Rpremium-grade unleaded gasoline
RE85 fuel
Ra mixture of E85 fuel and premium-grade
unleaded gasoline
iFlexible Fuel vehicles can be recognized by
the Ethanol up to E85 sticker on the inside of
the fuel filler flap.
Fuel consumption
The energy content of E85 fuel is less than that
of the same amount of premium-grade gasoline.
The amount of fuel consumed when operating
the vehicle with E85 fuel is therefore higher than
with premium-grade gasoline.
Maintenance
Inform your authorized Mercedes-Benz Center
that you are operating or have operated the
vehicle with E85 fuel.
Low outside temperatures
If the outside temperature is below 32 ‡(0 †),
the starting procedure can take noticeably lon-
ger when operating with E85 fuel.
E85 fuel is not suitable for use at outside tem-
peratures under -4 ‡ (-20 †).
DEF
Important safety notes
Comply with the important safety notes for ser-
vice products when handling DEF (Ypage 433).
DEF is a water-soluble fluid for the exhaust gas
aftertreatment of diesel engines. It is:
Rnot poisonous
Rcolorless and odorless
Rnot flammable
When you open the DEF container, small
amounts of ammonia vapor may be released.
Ammonia vapors have a pungent odor and are
particularly irritating to the skin, to mucous
membranes and to the eyes. You may experi-
ence a burning sensation in your eyes, nose and
throat. Coughing and watering of the eyes are
possible.
Do not inhale ammonia vapors. Fill the DEF tank
only in well-ventilated areas.
436Service products and filling capacities
Technical data