Well,
for
those
of
you
lucky
enough
to
own
one
of
Stuttgart's
classiest
sports
coupes,
one
aspect
of
these
cars
has
always
been
somewhat
tempermental;
the
beloved
seatbelt
extender
mechanism.
More
often
than
not,
the
extender
arm
is
broken
due
to
abuse
or
by
accident
caused
either
by
pulling
on
the
seatbelt
too
hard,
too
fast
or
simply
entering
or
exiting
the
vehicle
before
the
arm
has
had
a
chance
to
fully
retract.
For
those
of
you
who
simply
have
a
broken
arm,
well
you're
lucky
as
this
part
is
simple
to
replace
as
it
simply
pulls
out
and
you
insert
the
new
arm
back
into
the
gear
drive.
However,
another
scenario
poses
a
more
difficult
remedy.
After
years
of
use,
the
gear
drive
inside
the
seatbelt
extender
mechanism
eventually
wears
and
strips
preventing
the
plastic
arm
from
extending
fully
if
at
all.
In
the
past,
the
only
cure
for
this
situation
was
to
replace
the
entire
assembly,
as
that
is
how
it
is
sold
by
Mercedes;
as
a
single
part
encompassing
the
seatbelt
extender
motor,
bracket,
and
gears.
Recently,
an
aluminum
gear
has
been
made
available
from
Autolux,
Inc.
I
was
able
to
contact
George
Murphy
at
Performance
Analysis
who
sent
me
an
aluminum
gear
to
replace
the
flimsy
plastic
fiber
gear
that
the
factory
uses.
I
decided
to
try
this
out
and
was
pleased
that
someone
had
come
up
with
not
only
a
direct
replacement
part,
but
one
that
was
much
better
than
the
flimsy
original
equipment
replacement.
The
car
in
this
demonstration
is
a
1987
560SEC
AMG
(yes,
a
true
AMG
car
with
the
wheels,
engine,
bodywork,
the
whole
nine
yards).
The
vehicle
belongs
to
my
friend
Richard
Giampietro.
He
brought
the
car
to
me
to
have
me
diagnose
and
fix
this
system.
After
a
careful
examination,
I
noticed
that
this
problem
was
actually
twofold.
First
off,
his
retractor
arm
was
showing
signs
of
wear
as
the
plastic
teeth
were
worn
in
many
places.
Secondly,
as
with
any
gear
setup,
one
worn
gear
usually
means
there's
probably
another
gear
worn
out
somewhere.
I
decided
to
be
conservative
at
first
and
ordered
a
new
arm.
After
installing
the
arm,
it
retracted
okay
but
wouldn't
extend
properly.
I
knew
now
that
this
was
going
to
be
more
involved.
The
solution
would
be
to
open
the
side
panel
and
remove
the
motor
assembly
to
replace
the
worn
components.
For
starters,
the
only
tools
you'll
need
for
this
operation
is
a
small
flathead
screwdriver,
a
#1
Phillips
and
#2
Phillips
screwdriver,
a
17mm
socket
wrench,
an
8mm
open-ended
wrench
and
some
patience.
First,
remove
the
lower
seat
cushion
by
pressing
the
red
tabs
in
opposite
directions
while
lifting
the
seat
cushion
upwards
at
the
same
time.
Next,
remove
the
seatback
cushion
by
pressing
the
metal
tab
located
Next,
remove
the
lower
screw
holding
the
lower
portion
of
the
side
on
the
bottom
of
the
seat
cushion
and
push
upwards
firmly.
Place
the
panel
in
place.
This
screw
is
seen
by
simply
pulling
aside
the
black
two
cushions
outside
the
car
and
start
examining
the
side
panel.
First,
noise
insulation
material.
remove
the
3-#1
Phillips
screws
that
hold
the
decorative
chrome
plate
on
the
door
sill.
Next,
remove
the
assist
handle
by
inserting
a
#2
-
Phillips
screwdriver
Next,
pry
off
the
panel
cover
plate
which
will
reveal
the
harness
for
into
the
hole
at
the
bottom
of
the
handle.
Also,
using
a
small
flathead
the
power
window
switch
connection.
This
is
what
the
panel
looks
screwdriver,
pry
up
the
power
window
switch
and
remove
the
black
like
once
it
is
removed.
#2
-
Phillips
screw
pointing
downward
inside
the
black
case.
This
small
screw
attaches
the
black
casing
to
the
rest
of
the
assist
handle.
Remove
all
of
the
6
#2-
Phillips
screws
which
hold
the
wire
connection
terminals
together.
Don't
worry
about
marking
the
wires'
positions
as
all
of
the
wires
on
both
sides
of
the
terminal
block
are
color-coded
(Mercedes
REALLY
should
have
used
a
simply
6-pin
Molex
connector
here
instead).
Now,
you
can
remove
the
side
panel
completely.
Place
it
aside
by
extending
the
seat
belt
completely
to
give
you
more
slack.
Remember
that
the
seat
belt
is
still
looped
through
the
outlet
in
the
side
panel
so
it
isn't
still
free
from
the
vehicle
but
you'll
have
plenty
of
slack
in
the
seat
belt
to
allow
you
to
put
the
panel
aside.
Next,
you
must
remove
the
seatbelt
extender
gear
assembly.
Although
it
is
completely
possible
to
replace
the
fiber
gear
with
the
assembly
still
in
place,
it
is
MUCH
easier
to
work
with
the
unit
on
a
flat
surface;
besides,
it
only
involves
removing
3
screws
and
1
bolt;
all
of
which
are
easily
accessible.
Remove
the
3
-
#2
Phillips
screws
as
seen
on
the
next
illustration.
Next,
pull
the
assembly
from
the
car
and
place
it
on
a
flat
surface.
Also,
disconnect
the
2
Molex
electrical
connectors
on
the
end
of
the
Remove
the
e-clip
holding
the
gear
assembly
housing.
Also,
assembly.
Notice
above
that
my
finger
is
pointing
to
where
the
17mm
remove
the
spring
tensioning
bolt
using
an
8mm
wrench
and
head
bolt
is
located.
Remove
this
bolt
with
the
socket
wrench.
Also,
noting
its
relative
position.
notice
that
approximately
3
inches
below
my
finger
is
another
Phillips
#2
screw.
Remove
this
screw
as
well.
Finally,
remove
these
last
2
Phillips
#2
screws
located
near
the
rear
of
the
assembly.
Shown
above
is
the
new
aluminum
gear
installed
within
the
plastic
Notice
the
stripped
fiber
gear
causing
the
arm
to
not
extend...
housing.
Reinstall
the
e-clip
which
holds
the
plastic
assembly
in
place
and
reinstall
the
metal
spring,
tensioning
it
with
the
8mm
head
bolt.
Finally,
replace
all
the
removed
items
on
the
vehicle.
The
installation
is
exactly
the
reverse
of
removal.
Once
everything
is
installed,
insert
the
extender
arm
into
the
motor
drive
slot
and
adjust
how
far
it
retracts
by
adjusting
the
clip
on
the
extender
arm
itself
shown
below.
The
position
of
this
clip
determines
how
far
inward
the
arm
will
retract.
That's
it!
The
entire
operation
took
me
about
an
hour
and
the
end
result
is
an
extender
assembly
that
works
like
new.
-
contributed
by
Satish
Tummala
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