check engine MERCEDES-BENZ M-Class 2013 W166 Owner's Guide

Using the SmartKey:
R
Make sure that the ignition is switched on.
R When the vehicle is stationary, depress the
brake pedal and keep it depressed.
R Shift to neutral N.
R Release the brake pedal.
R If the electric parking brake is engaged,
release it.
R Switch off the ignition and leave the
SmartKey in the ignition lock.
Using KEYLESS-GO:
R Make sure that the ignition is switched on.
R When the vehicle is stationary, depress the
brake pedal and keep it depressed.
R Engage park position P.
R Release the brake pedal.
R Remove the Start/Stop button from the
ignition lock.
R Insert the SmartKey into the ignition lock.
R Switch on the ignition.
R Depress the brake pedal and keep it
depressed.
R Shift to neutral N.
R Release the brake pedal.
R If the electric parking brake is engaged,
release it.
R Switch off the ignition and leave the
SmartKey in the ignition lock.
Engaging drive position D X
When the vehicle is stationary, depress the
brake pedal.
X Push the DIRECT SELECT lever down past
the first point of resistance. Transmission positions
0005
Par
kposition
Do not shift the transmission into
position P(Ypage 179) unless the
vehicle is stationary. The parking
lock should not be used as a brake
when parking .Always apply the
electronic parking brake in
additio nto the parking lock in order
to secure the vehicle.
If the vehicle electronics are
malfunctioning, the transmission
may be locked in position P. Have
the vehicle electronics checked
immediately at a qualified
specialist workshop.
The automatic transmission shifts
to Pautomatically if you:
R remove the SmartKey
R switch off the engine when in R
or Dand open one of the front
doors 0007
Reverse gear
Only shift the transmission to
R
when the vehicle is stationary. Automatic transmission
167Driving and parking Z

Problems with the transmission
Problem Possible causes/consequences and
0001 Solutions
The transmission has
problems shifting gear. The transmission is losing oil.
X
Have the transmission checked at a qualified specialist
workshop immediately. The acceleration ability
is deteriorating.
The transmission no
longer changes gear. The transmission is in emergency mode.
It is only possible to shift into
secondgear and reverse gear.
X Stop the vehicle.
X Shift the transmission to position P.
X Switch off the engine.
X Wait at least ten seconds before restarting the engine.
X Shift the transmission to position Dor R.
If D is selected, the transmission shifts into secondgear; ifRis
selected, the transmission shifts into reverse gear.
X Have the transmission checked at a qualified specialist
workshop immediately. Transfer case
! Performance tests may only be carried
out on a 2-axle dynamometer. The brake
system or transfer case could otherwise be
damaged. Contact a qualified specialist
workshop for a performance test.
! Because ESP ®
is an automatic system,
the engine and ignition must be switched
off (SmartKey in position 0or 1or Start/
Stop button in position 0or 1) when the
electric parking brake is being tested on a
brake dynamometer (maximum
10 seconds).
Braking triggered automatically by ESP ®
may seriously damage the brake system.
! Vehicles with 4MATIC must not be towed
with either the front or the rear axle raised,
as doing so will damage the transmission.
This section is only valid for vehicles with 4-
wheel drive (4MATIC). Power is always
transmitted to both axles. Refueling
Important safety notes
G
WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and
explosion.
You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable, the auxiliary heating before
refueling. G
WARNING
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. Refueling
173Driving and parking
Z

The position of the fuel filler cap is displayed
0012 in the instrument cluster. The arrow
next to the filling pump indicates the side of
the vehicle.
Opening X
Switch the engine off.
X Remove the SmartKey from the ignition
lock.
X KEYLESS-GO: open the driver’s door.
This corresponds to key position 0: "key
removed".
The driver’s door can be closed again.
X Press the fuel filler flap in the direction of
arrow 0002.
The fuel filler flap swings up.
X Turn the fuel filler flap counter-clockwise
and remove it.
X Insert the fuel filler cap into the holder
bracket on the inside of filler flap 0003.
X Completely insert the filler neck of the fuel
pump nozzle into the tank, attach and
refuel.
X Only fill the tank until the pump nozzle
switches off.
i Do not add any more fuel after the pump
stops filling for the first time. Otherwise,
fuel may leak out.
Closing X
Replace the cap on the filler neck and turn
clockwise until it engages audibly.
X Close the fuel filler flap.
i Close the fuel filler flap before locking the
vehicle.
i If you are driving with the fuel filler cap
open, the 0012reserve fuel warning lamp
flashes.
In addition, the 0010Check Engine warning
lamp may light up (Y page 325).
Am essage appears in the multifunction
display ( Ypage 301). For further information on warning and
indicator lamps in the instrument cluster,
see (Y
page 325). Refueling
175Driving and parking Z

DEF (BlueTEC vehicles only)
Important notes on use To function properly, BlueTEC exhaus
tgas
aftertreatment must be operated with the
reducing agent DEF.
When the supply of DE Fis almost used up,
the Check Additive See Operator's Manual message is shown in the
multifunction display.
When the DEF supply drops to a minimum, the
Remaining Starts: 16 message is shown
in the multifunction display.
If the Remaining Starts: 16 message
appears in the multifunction display, you can
start the engine another 16 times. If DEF is
not refilled, you will subsequently be unable
to start the engine. Add DEF tank with
approximately 1gal (3. 8l) DEF. Have the DEF
tan krefilled at a qualified specialist
workshop.
i If you drive the vehicle faster than
10 mph (16 km/h), the Check Additive See Operator's Manual message goes
out after approximately one minute.
If the outside temperature is lower than
12 ‡ (0020 11) †, damage may occur when
adding DEF. If DEF is frozen and there is an
active warning indicator, it may not be
possible to add DEF. Park the vehicle in a
warmer place, e.g. in a garage, until DEF has
become fluid again. It will then be possible to
add DEF again. Alternatively, have the DEF
tank refilled at a qualified specialist
workshop.
Further information about BlueTEC exhaust
gas aftertreatment and DEF is available at any
authorized Mercedes-Benz Center. Important safety notes on the refilling
procedure DEF is a water-soluble fluid for the exhaust
gas aftertreatment of diesel engines. It is:
R
not poisonous
R colorless and odorless
R not 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
experience a burning sensation in you reyes,
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.
DEF must not come into contact with your
skin, eyes or clothing and mus tnot be
swallowed. Keep DEFa way fromchildren.
If you or other persons come into contact with
DEF, observe the following:
R Rinse DEF from your skin immediately with
soap and water.
R If DEF comes into contact with your eyes,
immediately rinse them thoroughly with
clean water. Seek medical assistance
without delay.
R If DEF has been swallowed, rinse your
mouth out immediately. Drink plenty of
water. Seek medical assistance without
delay.
R Change out of clothing contaminated with
DEF immediately.
! Only use DEF in accordance with
ISO 22241. Do not mix any additives with
DEF, and do not dilute DEF with water. This
may destroy the BlueTEC exhaust gas
aftertreatment system.
! The vehicle must be parked on level
ground to fill the DEF tank. The DEF tank
can only be filled as intended with the
vehicle parked on a level surface. This
avoids false level readings. Filling the tank Refueling
177Driving and parking Z

Closing the DEF filler cap
X
Install DEF filler cap 0003on the filler neck
and turn it clockwise.
X To close the fuel fille rflap, press it in the
direction of arrow 0002.
X Drive faster than 10 mph (16 km/h).
The Check Additive See Operator's Manual message goes out after
approximately one minute.
i If the Check Additive See Operator's Manual message continues
to be shown in the multifunction display,
you must add more DEF. Parking
Important safety notes
G
WARNING
If flammable materials such as leaves, grass
or twigs are exposed to prolonged contac tto
parts of the exhaust system that heat up, they
could ignite. There is a risk of fire.
Park the vehicle so that no flammable
materials come into contact with parts of the
vehicle which are hot. Take particular care not
to park on dry grassland or harvested grain
fields. G
WARNING
If you switch off the ignition while driving,
safety-relevant function sare only available
with limitations, or not at all.T his could affect,
for example, the power steering and the brake
boosting effect.Y ou will require considerably more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving.
G
WARNING
If you leave children unsupervised in the
vehicle, they could set it in motion by, for
example:
R releasing the parking brake
R shifting the automatic transmission out of
the parking position P
R starting the engine.
They could also operate the vehicle's
equipment. There is a risk of an accident and
injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
! Always secure the vehicle correctly
against rolling away.O therwise, the vehicle
or its drivetrai ncould be damaged.
To ensure that the vehicle is secured against
rolling away unintentionally:
R the electric parking brake must be applied.
R the transmission must be in position Pand
the SmartKey must be removed from the
ignition lock.
R on steep uphill or downhill gradients, turn
the front wheels towards the curb.
R on steep uphill or downhill gradients, the
front axle of an empty vehicle must be
secured, for example with awheel chock.
R on steep uphill or downhill gradients, the
rear axle of a laden vehicle must be
additionally secured, for example with a
wheel chock. Parking
179Driving and parking Z

Limited braking performance on salt-
treated roads
If you drive on salted roads, a layer of salt
residue may for
monthe brake discs and
brake pads. This can result in a significantly
longer braking distance.
R Brake occasionally to remove any possible
salt residue. Make sure that you do not
endanger other road users when doing so.
R Carefully depress the brake pedal and the
beginning and end of a journey.
R Maintain a greater distance to the vehicle
ahead.
Servicing the brakes !
If the red brake warning lamp lights up in
the instrumentc luster and you hear a
warning tone while the engine is running,
the brake fluid level may be too low.
Observe additional warning messages in
the multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked
immediately. This work should be carried
out at a qualified specialist workshop.
! A function or performance test should
only be carried out on a2-axle
dynamometer. If you are planning to have
the vehicle tested on such a dynamometer,
contact an authorized Mercedes-Benz
Center to obtain further information first.
Otherwise, you could damage the drive
train or the brake system.
! Because ESP ®
is an automatic system,
the engine and ignition must be switched
off (SmartKey in position 0or 1or Start/
Stop button in position 0or 1) when the
electri cparking brake is being tested on a
brake dynamomete r(maximum
10 seconds).
Braking triggered automatically by ESP ®
may seriously damage the brake system. All checks and maintenance work on the
brake system must be carried out at a
qualified specialist workshop
.Consult a
qualified specialist workshop to arrange this.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop.
If the brake system has only been subject to
moderate loads, you should test the
functionality of your brakes at regular
intervals. To do so, press firmly on the brake
pedal when driving at a high speed. This
improves the grip of the brake pads.
You can find a description of Brake Assist
(BAS) on (Y page 67) or of BAS PLUS on
(Y page 67).
Mercedes-Benz recommends that you only
have brake pads/linings installed on your
vehicle which have been approved for
Mercedes-Benz vehicles or which correspond
to an equivalent quality standard. Brake
pads/linings which have not been approved
for Mercedes-Benz vehicles or which are not
of an equivalent quality could affect your
vehicle's operating safety.
Mercedes-Benz recommends that you only
use brake fluid that has been specially
approved for your vehicle by Mercedes-Benz,
or which corresponds to an equivalent quality
standard. Brake fluid which has not been
approved for Mercedes-Benz vehicles or
which is not of an equivalent quality could
affect your vehicle's operating safety.
High-performance brake system for
AMG vehicles The high-performance brake system is
installed only on the ML 63 AMG.
The high-performance brake system is
designed for heavy loads. This may lead to
noise when braking. This will depend on:
R Speed
R Braking force
R Environmental conditions, such as
temperature and humidity 184
Driving tipsDriving and parking

The wear of individual components of the
brake system, such as the brake pads/linings
or brake discs, depends on the individual
driving style and operating conditions.
For this reason, it is impossible to state a
mileage that will be valid under all
circumstances. An aggressive driving style
will lead to high wear. You can obtain further
information about this from your authorized
Mercedes-Benz Center.
New and replaced brake pads and discs only
reach their optimum braking effect after
several hundred kilometers of driving.
Compensate for this by applying greater force
to the brake pedal. Keep this in mind, and
adapt your driving and braking accordingly
during this break-in period.
Excessive heavy braking results in
correspondingly high brake wear. Observe
the 000A brake wear warning lamp in the
instrument cluster and note any brake status
messages in the multifunction display.
Especially for high performance driving, it is
important to maintain and have the brake
system checked regularly. Driving on wet roads
Hydroplaning If water has accumulated to a certain depth
on the road surface, there is a danger of
hydroplaning occurring, even if:
R you drive at low speeds.
R the tires have adequate tread depth.
For this reason, in the event of heavy rain or
in conditions in which hydroplaning may
occur, you must drive in the following
manner:
R lower your speed.
R avoid ruts.
R brake carefully. Driving on flooded roads !
Do not drive through flooded areas.
Check the depth of any water before driving
through it. Drive slowly through standing
water. Otherwise, water may enter the
vehicle interior or the engine compartment.
This can damage the electronic
components in the engine or the automatic
transmission. Water can also be drawn in
by the engine's air suction nozzles and this
can cause engine damage.
i Vehicles with the AIRMATIC package:
set the raised level before driving through
standing water.
Off-road fording !
Under no circumstances should you
accelerate before entering the water. The
bow wave could cause water to enter and
damage the engine and other assemblies.
! Do not open any of the vehicle's doors
while fording. Otherwise, water could get
into the vehicle interior and damage the
vehicle's electronics and interior
equipment. 0002
Fording depth Driving tips
185Driving and parking Z

damaging the vehicle, make sure there is
always sufficient ground clearance.
R Check that items of luggage and loads are
stowed safely and are well secured
(Y page 337).
R Always keep the engine running and in gear
when driving on a downhill gradient.
Activate DSR( Ypage 246).
R Always keep the doors, tailgate, windows
and sliding sunroof closed while driving.
R Adapt your speed to the terrain. The
rougher, steeper or more ruts on the
terrain, the slower your speed should be.
R Drive slowly and at an even speed through
the water. Ensure that a bow wave does not
form as you drive.
R Drive with extreme care on unfamiliar off-
road routes where visibility is poor. For
safety reasons, get out of the vehicle first
and survey the off-road route.
R Look out for obstacles, such as rocks,
holes, tree stumps and furrows.
R Check the depth of water before fording
rivers and streams.
R When fording, do not stop and do not
switch off the engine.
R On sand, drive quickly to overcome the
rolling resistance. Otherwise the vehicle's
wheels could become stuc kinloose
ground.
R Do not jump with the vehicle as this will
interrupt the vehicle's propulsion.
R Always keep the engine running and in gear
when driving on a slope.
R Do not shift the automatic transmission to
transmission position N.
i Do not use the HOLD function when
driving off-road, on steep uphill or downhill
gradients or on slippery or loose surfaces.
The HOLD function cannot hold the vehicle
on such surfaces. Checklist before driving off-road !
If the engine oil warning lamp lights up
while the vehicle is in motion, stop the
vehicle in a safe place as soon as possible.
Check the engine oil level. The engine oil
warning lamp warning must not be ignored.
Continuing the journey while the symbol is
displayed could lead to engine damage.
X Engine oil level: check the engine oil level
and add oil if necessary.
When driving on steep gradients, the
engine oil level must be sufficiently high to
ensure a correc toil supply in the vehicle.
X DEF tank (BlueTEC vehicles): check the
fluid level and, if necessary, refill to the
maximum (13 l) (Y page 177).
X Wheel-changing tool kit: check that the
jac kis working and make sure you have the
lug wrench, a robust tow cable and a folding
spade in the vehicle.
X Wheels and tires: check the tire tread
depth and tire pressure.
X Check for damage and remove any foreign
objects, e.g. small stones, from the
wheels/tires.
X Replace any missing valve caps.
X Replace dented or damaged wheels.
X Rims: dented or bent rims can result in a
loss of tire pressure and damage the tire
bead. Therefore, check your rims before
driving off-road and replace them as
required.
Checklist after driving off-road !
If you detect damage to the vehicle after
driving off-road, have the vehicle checked
immediately at a qualified specialist
workshop.
X Deactivate DSR (Y page 246).
X Vehicles with the AIRMATIC package:
lower the vehicle to a ride height suitable
for the road conditions, e.g. to the
highway/high-speed level. 188
Driving tipsDriving and parking

X
Clean the headlamps and rear lights and
check for damage.
X Clean the fron tand rea rlicense plates.
X Clean the wheels/tires with a water jet and
remove any foreign objects.
X Clean the wheels, wheel housings and the
vehicle underside with a water jet; check
for any foreign objects and damage.
X Check whether twigs or other parts of
plants have become trapped. These
increase the risk of fire and can damage
fuel pipes, brake hoses or the rubber
bellows of the axle joints and propeller
shafts.
X After the trip, examine without fail the
entire undercarriage, wheels, tires, brakes,
bodywork structure, steering, chassis and
exhaust system for damage.
X After driving for extended periods across
sand, mud, gravel, water or in similarly dirty
conditions, have the brake discs, wheels,
brake pads/linings and axle joints checked
and cleaned.
X If you detect strong vibrations after off-road
travel, check for foreign objects in the
wheels and drive train and remove the mif
necessary .Foreign objects can disturb the
balance and cause vibrations.
Driving over rough terrain places greater
demands on your vehicle than driving on
normal roads. After driving off-road, check
the vehicle. This allows you to detect damage
promptly and reduce the risk of an accident
to yourself and other road users.
Driving on sand Observe the following rules when driving on
sand:
R vehicles with the AIRMATIC package:
select a raised vehicle level.
R avoid high engine speeds.
R select a shift range appropriate to the
terrain. R
drive quickly to overcom ethe rolling
resistance. Otherwise the vehicle's wheels
could become stuck in loose ground.
R drive in the tracks of other vehicles if
possible. Make sure that:
-the tire ruts are not too deep.
- the sand is sufficiently firm.
- the ground clearance of the vehicle is
sufficient.
Tire ruts and gravel roads !
Check that the ruts are not too deep and
that your vehicle has sufficient clearance.
Otherwise, your vehicle could be damaged
or bottom out and get stuck.
Observe the following rules when driving
along ruts in off-road terrain or on roads with
loose gravel:
R vehicles with the AIRMATIC package:
select a raised vehicle level.
R avoid high engine speeds.
R select shift range 1.
R drive slowly.
R where ruts are too deep, drive with the
wheels of one side on the center grassy
area, if possible.
Crossing obstacles !
Obstacles could damage the floor of the
vehicle or components of the chassis. Ask
passengers for guidance when driving over
large obstacles. The passenger should
always keep a safe distance from the
vehicle when doing so in order to avoid
injury as a result of unexpected vehicle
movements. After driving off-road or over
obstacles, check the vehicle for possible
damage, especially to the underbody and
the components of the chassis. Driving tips
189Driving and parking Z

0002 0003
Vehicles with the
ON&OFFROAD
package
Highway level 22° 22°
Off-road level 1 25° 24°
Off-road level 2 28° 27°
Off-road level 3 29° 29°
R
Observe the rules on off-road driving.
R Do not drive at an angle on slopes, inclines
or gradients, bu tinstead follow the direct
line of fall .The maximum gradient-climbing
capability of your vehicle is 100%, which
corresponds to an approach/departure
angle of 45°. Note that the climbing ability
of your vehicle depends on the terrain
conditions.
R Before tackling steep downhill gradients,
select shift range 1.
R Drive slowly.
R Avoid high engine speeds –drive at an
appropriate engine speed (maximum
3,000 rpm).
R When driving downani ncline, make use of
the engine's braking effect. Observe the
engine speed; do not overre vthe engine.
R Check the brakes after prolonged off-road
driving.
i Hill start assist will aid you when pulling
away on a hill.
For more information, see "Hill start assist"
(Y page 161).
Do not switch to transmission position N
when driving off-road. If you try to brake the
vehicle using the service brake, you could
lose control of the vehicle. If the gradient is
too steep for your vehicle, drive back down in
reverse gear. Maximum gradient-climbing capability On good road surfaces the maximum
gradient-climbing capability of your vehicle is
100%, which corresponds to an approach/
departure angle of 45°. Note that the
vehicle's gradient-climbing capability
depends on the off-road conditions.
Accelerate carefully and make sure that the
wheels do not spin when driving on steep
terrain.
i
If the load on the front axle is reduced
when pulling away on a steep uphill slope,
the front wheels have a tendency to spin.
4ETS recognizes this and brakes the
wheels accordingly. The rear wheel torque
is increased, making it easier to drive off.
Hilltops When driving up an uphill gradient, slightly
reduce pressure on the accelerator
immediately before reaching the brow of the
hill. Use the vehicle's own impetus to drive
over the top of the hill.
This style of driving prevents:
R
the vehicle from lifting off the ground on the
brow of a hill
R the vehicle from traveling too quickly down
the other side
Driving downhill R
Drive slowly.
R Do not drive at an angle down steep
inclines. Steer into the line of fall and drive
with the front wheels aligned straight.
Otherwise, the vehicle could slip sideways,
tip and rollover.
R Before tackling steep downhill gradients,
select shift range 1.
R Activate DSR. If this is not sufficient, brake
gently. When doing so, make sure that the
vehicle is facing in the direction of the line
of fall.
R Check that the brakes are working normally
after a long downhill stretch. Driving tips
191Driving and parking Z