Mercedes-Benz 212 Sedan E-Class Service Manual page 87

Passive safety
Crash-active engine hood
The crash-active engine hood is installed as standard
equipment on model series 212 in order to reduce the
accident loads for pedestrians and cyclists and to
meet the legal requirements in Europe and Japan.
In the event of a collision, e.g. with a pedestrian, this
hood can be triggered by sensors and raised in the
area of the A-pillar. Raising the engine hood creates
additional deformation space in the event of an impact
with the head of the pedestrian and thereby reduces
the accident loads.
If the vehicle collides with a pedestrian, an extensive
sensor system in the front bumper actuates the
spring-loaded engine hood lifters near the hood
hinges, which lift the hood by approx. 50 mm. The
additional space gained between the engine hood and
components in the engine compartment results in an
efficient and gentle deceleration when impacted by
the pedestrian's head.
The deformation properties of the hood were devel-
oped specifically to meet these requirements. The use
of aluminum and homogeneous reinforcement on the
inside of the engine hood further reduce the loads
during an impact.
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Introduction of the New E-Class, Model Series 212 Sedan
b
– This printout will not be recorded by the update service. Status: 01 / 2009 –
The function sequence occurs in the following stages:
1 During an impact, sensors installed in the bumper
and on the flexural member generate acceleration
signals, which are relayed to the supplemental
restraint system control unit.
2 When it receives the acceleration signals, the
supplemental restraint system control unit
activates the spring-loaded engine hood lifters at
the hinges of the engine hood on each side.
3 This triggers the spring-loaded engine hood lifters
and the hood is raised by a distance of approx.
50 mm in the area of the A-pillar on both sides.
Crash-active engine hood (triggered)
i Note
Never attempt to press the engine hood back
down at the rear when it has triggered. This could
cause damage to the hood.
P88.40-2852-00