Panasonic NN-K543WF, Service Manual

Page: 10 / 37

5.1. Magnetron
1. Discharge high voltage charge.
2. Remove 1 screw holding air guide A.
3. Remove 1 screw holding air guide F.
4. Remove 1 screw holding themistor.
5. Disconnect 2 high voltage lead wires from magnetron
filament terminals.
6. Remove 4 screws holding the magnetron.
NOTE:
After replacement of the magnetron, tighten mounting
screws properly making sure there is no gap between
the
waveguide and the magnetron to prevent
microwave leakage.
CAUTION
When replacing the magnetron, be sure the antenna gasket is in
place.
5.2. Digital programmer circuit
(D.P.C) and membrane key
board.
NOTE:
Before handing the D.P.C ensure that your body is
connected to ground to discharge any electric charge.
1. Disconnect all connectors from D.P.C.
2. Remove 1 screw holding escutcheon base and slide the
escutcheon base upward slightly.
3. Remove 1 screw holding D.P.C.
4. Release lock of connector CN6 by pushing both levels to
inside and pull them upward, and remove flat cable of
membrane keyboard.
5. Separate D.P.C board from tabs on the escutcheon base
and remove D.P.C board.
To replace membrane key board
6. Push the upper part of key board (display window portion)
from back of escutcheon base and peel off escutcheon
sheet
and membrane key board completely from
escutcheon base.
NOTE:
1. The membrane key board is attached to the
escutcheon base with double faced adhesive tape.
Therefore, applying hot air such as using a hair dryer is
recommended for smoother removal.
2. When installing new membrane key board, make
sure that the surface of escutcheon base is cleaned
sufficiently so that any problems (shorted contacts or
uneven surface) can be avoided.
3. Alignment position of membrane key board is as
follows;
Membrane key board: Right and upper edges
Escutcheon sheet: Right and upper edges
5 DISASSEMBLY AND PARTS REPLACEMENT
PROCEDURE
10
NN-S453WF