coolant reservoir MERCEDES-BENZ M-Class 2012 W166 Owner's Manual

Furth
erinfor mationonengi neoil
(Y page 388). Che
cking and adding otherserv ice
pr odu cts
Checkin gth ecoolant level On
lyche ckthecoo lant level when theveh icle
is on alevel surface and theeng inehas cooled
down .
X Turn theSm artKey toposit ion
2 (Y page 139)intheign itio nlock .
On veh icleswith KEYLE SS-GO ,pres sth e
St art /S topbutt ontwic e(Ypage 139).
X Check thecoolant temperaturegauge in
the multifun ction display.
The coolant temperaturemustbebelow
158 ‡(70 †). G
WARN
ING In
order toavoid anypoten tiallyserious burns:
R use extreme caution whenopenin gthe
hood ifther eare any signs ofsteam or
coolant leakingfromthecoolin gsystem ,or
if the coolant temperaturedisplay indicates
that thecoolant isoverheat ed.
R do not remov ethe pressure caponthe
coolant reservoirifthe coolant temperature
is above 158‡(70 †). Allow theengine to
cool downbefore removin gthe cap. The
coolant reservoircon tains hotfluid andis
under pressure.
R using arag, slowly turnthecap
approximat ely1
/ 2 turn
torelieve excess
pressure. Ifopened immediately, scalding
hot fluid andsteam willbeblown outunder
pressure.
R do not spill antifreeze onhot engine parts.
An tifr eeze contains ethylene glycolwhich
may burn ifit comes intocontact with hot
engine parts. X
Slowly turncap:half aturn count er-
clock wiseandallow excesspressure to
escape.
X Turn cap:furth ercount er-clockwise and
remove it.
If the coolant isat the level ofmarker bar
= inthe filler neck when cold,there is
enough coolant incoolant expansion
tank ;.
If the coolant isapproximat ely0.6 in
(1.5 cm)above marker bar=inthe filler
neck when warm, thereisenough coolant
in coolant expansion tank;.
X Ifneces sary,addcoolant thathasbeen
test edand approved byMercedes- Benz.
X Replace cap:and turn itclock wiseasfar
as itwill go.
For furth erinfor mation oncoolant ,see
(Y page 389).
Windshield washersystemand
headla mpcleaning system The
washer fluidreservo iris used forboth the
windshield washersystemandtheheadlamp
cleanin gsystem. i
Vehicle
compon entsand their servic e
product smust match.You should,
theref ore,only useproduct sthat have been
test edand approved byMercedes- Benz.
Inf ormation ontest edand approved
product scan beobtained atany authorized
Mercedes- BenzCenter oron the Internet at
htt p://ww w.mbu sa.com (USAonly). Engine
compartment
315Maintenance and care Z