Replacing Parts; Function Switch; Thermal Fuse - Philips PM2521 Service Manual

58
2.2.
REPLACING PARTS
2.2.1.
Liquid
crystal display
(fig.
44
item
1),
display unit
N3
(fig.
44
item
2),
interconnection rubber
(fig.
44
item
3)
or function knob
(fig.
44
item
4).
—
Remove
the
front assembly.
—
Remove
the
six
screws and
the screening
plate of the front assembly,
(fig.
44
item
6).
NOTE:
The
potentiometer
R502
can
now
be
removed.
—
Remove
the function knob by
bending out the
four hooks
of the
front
plate, (only for replacing
the function
knob)
(fig.
44
item
8).
-
Remove
the
three screws from
the display unit cover
and
the cover
itself, (fig.
44
item
5).
—
Replace the
defective
component
and mount
the L.C.D.
unit again
as described above.
NOTE
1:
Make
sure that the
L
C.D., the display unit
cover and
the interconnection
rubber
are
placed
in the
most
right
hand
position,
(fig.
44
item
7).
NOTE
2:
Do
not
touch
the contacts of
the
L.
C.D., the interconnection
rubber
and
the display unit
N3
with
the
fingers.
2.2.2.
Function
switch,
(fig.
42)
Remove
the
top-
and bottom
cover.
Remove
also the front assembly.
-
Bend
out
the
two
hooks and remove
the
printed-circuit board,
(fig.
42
item
4).
—
The
function switch
consist
of:
—
2
slide
bodies
—
4
springs
—
4
switch
contacts
—
Remove
the screws and
nuts from
the
slide
bodies.
The
bodies can
now
be
lifted
from
the
printed-circuit
board.
NOTE:
The
slide
body
is
stocked complete with
springs
and
switch
contacts.
2.2.3.
Thermal
fuse
—
Remove
the
bottom
cover.
—
Remove
the four screws
which
attach the screening
plate
of the transformer to the
bottom
cover,
(fig.
45
item
1 ).
-
Unsolder
the black wire connecting the transformer
with
the
screening,
(fig.
45
item
2).
-
Unsolder
the connections of the thermal
fuse.
(fig.
45a. item
1).
-
Replace the thermal
fuse
as
shown
in fig.
45a.
NOTE: Do
not
replace the
thermal
fuse with a piece of
wire as
this gives the
danger of
a
fire
hazard.