Coolant sensor MERCEDES-BENZ S550 2007 W221 Owner's Manual

379 Controls in detail
Instrument cluster
Tachometer
The red marking on the tachometer de-
notes excessive engine speed.
To help protect the engine, the fuel supply
is interrupted if the engine is operated
within the red marking.
Outside temperature indicator
The outside temperature indicator is on
the bottom left-hand side of the instru-
ment cluster.
The temperature sensor is located in the
front bumper area. Due to its location, the
sensor can be affected by road or engine
heat during idling or slow driving. There-
fore, the accuracy of the displayed temper-
ature can only be verified by comparison to
a thermometer placed next to the sensor,
not by comparison to external displays
(e.g. bank signs, etc.).When moving the vehicle into colder ambi-
ent temperatures (e.g. when leaving your
garage), you will notice a delay before the
lower temperature is displayed.
A delay also occurs when ambient temper-
atures rise. This prevents inaccurate tem-
perature indications caused by heat
radiated from the engine during idling or
slow driving.
Fuel gauge
The fuel gauge is on the left-hand side of
the instrument cluster (
page 28). Once
the fuel level has fallen below the reserve
mark, the yellow segment indicator for the
fuel reserve comes on (page 550).
!
Excessive coolant temperature triggers a
warning in the multifunction display
(
page 588).
The engine should not be operated with the cool-
ant temperature above 248°F (120°C), i.e. in
the red zone of the coolant temperature gauge.
Doing so may cause serious engine damage
which is not covered by the Mercedes-Benz Lim-
ited Warranty.
i
During severe operating conditions,
e.g. stop-and-go traffic, the coolant temperature
may rise close to 248°F (120°C), i.e. close to
the red zone of the temperature gauge.
!
Avoid driving at excessive engine speeds, as
it may result in serious engine damage that is not
covered by the Mercedes-Benz Limited Warran-
ty.
Warning!
G
The outside temperature indicator is not de-
signed to serve as an ice-warning device and
is therefore unsuitable for that purpose.
Indicated temperatures just above the freez-
ing point do not guarantee that the road sur-
face is free of ice. The road may still be icy,
especially in wooded areas or on bridges.