Undercarriage MERCEDES-BENZ M-Class 2015 W166 Owner's Manual

When driving off road or on unpaved roads,
check the vehicle's underside regularly. In
particular, remove parts of plants or other
flammable materials which have become
trapped. In the case of damage, contact a
qualified specialist workshop. G
WARNING
Modifications to electronic components, their software as well as wiring can impair their
function and/or the function of other net-
worked components. In particular, systems
relevant to safety could also be affected. As a
result, these may no longer function as inten-
ded and/or jeopardize the operating safety of
the vehicle. There is an increased risk of an
accident and injury.
Never tamper with the wiring as well as elec-
tronic components or their software. You
should have all work to electrical and elec-
tronic equipment carried out at a qualified
specialist workshop.
If you make any changes to the vehicle elec-
tronics, the general operating permit is ren-
dered invalid.
! There is a risk of damage to the vehicle if:
R the vehicle becomes stuck, e.g. on a high
curb or an unpaved road
R you drive too fast over an obstacle, e.g. a
curb or a hole in the road
R a heavy object strikes the undercarriage
or parts of the chassis
In situations like this, the body, the under-
carriage, chassis parts, wheels or tires
could be damaged without the damage
being visible. Components damaged in this way can unexpectedly fail or, in the case of
an accident, no longer withstand the strain
they are designed to.
If the underbody paneling is damaged,
combustible materials such as leaves,
grass or twigs can gather between the
underbody and the underbody paneling. If
these materials come in contact with hot parts of the exhaust system, they can catch
fire.
In such situations, have the vehicle
checked and repaired immediately at a
qualified specialist workshop. If on con-
tinuing your journey you notice that driving
safety is impaired, pull over and stop the
vehicle immediately, paying attention to
road and traffic conditions. In such cases,
visit a qualified specialist workshop. Declarations of conformity
Vehicle components which receive
and/or transmit radio waves USA:
"The wireless devices of this vehicle
comply with Part 15 of the FCC Rules. Oper-
ation is subject to the following two condi-
tions: 1) These devices may not cause harm-
ful interference, and 2) These devices must
accept any interference received, including
interference that may cause undesired oper-
ation. Changes or modifications not expressly
approved by the party responsible for com-
pliance could void the user’s authority to
operate the equipment."
Canada: "The wireless devices of this vehicle
comply with Industry Canada license-exempt
RSS standard(s). Operation is subject to the
following two conditions: (1) These devices
may not cause interference, and (2) These
devices must accept any interference, includ- ing interference that may cause undesired
operation of the device." Diagnostics connection
The diagnostics connection is only intended
for the connection of diagnostic equipment at a qualified specialist workshop. G
WARNING
If you connect equipment to the diagnostics
connection in the vehicle, it may affect the
operation of the vehicle systems. As a result, 28
Introduction

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 correct oil supply in the vehicle.
X DEF tank (BlueTEC vehicles): check the
level and top up if necessary (Y page 180).
X Tire-changing tool kit: check that the jack
is 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 work-
shop.
X Vehicles with the ON&OFFROAD pack-
age: activate the on-road program
(Y page 251).
X Deactivate the LOW RANGE off-road gear
(Y page 253).
X Deactivate DSR (Y page 250).
X Vehicles with the AIRMATIC package:
lower the vehicle to a ride height suitable
for the road conditions, e.g. to the high-
way/high-speed level. X
Clean the headlamps and rear lights and
check for damage.
X Clean the front and rear license 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 bel-
lows 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 them if
necessary. Foreign objects can disturb the
balance and cause vibrations.
Driving over rough terrain places greater
demands on your vehicle than driving on nor-
mal 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 ON&OFFROAD pack-
age: select off-road program 1
(Y page 251).
R Vehicles with the AIRMATIC package:
select a raised vehicle level.
R Avoid high engine speeds. Driving tips
193Driving and pa rking Z