Panasonic NN-S543WF, Service Manual

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DISASSEMBLY AND PARTS REPLACEMENT PROCEDURE
1. Magnetron
(A) Discharge the high voltage capacitors, as mentioned and shown on page 11.
(B) Remove 1 screw holding air guide c to magnetron.
(C) Disconnect 2 high voltage lead wires from magnetron filament terminals.
(D) Remove 4 screws holding the magnetron.
NOTE: After replacement of the magnetron, tighten mounting screws in an X
pattern, properly making sure there is no gap between the waveguide
and the magnetron to prevent microwave leakage.
2. Digital Programmer Circuit (DPC) and membrane key board.
NOTE: Be sure to ground any static electric charge built up on your body before
handling the DPC.
(A) Disconnect all connectors from D.P.C.
(B) Slide the escutcheon base upward slightly.
(C) Remove 1 screws holding DPC
To replace membrane key board
(F) 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
3. Low voltage transformer and/or power relays (RY1, RY2)
NOTE: Be sure to ground any static electric charge built up on your body before
handling the DPC.
(A) Using solder wick or a desoldering tool and 30W soldering iron, carefully
remove all solder from the terminal pins of the low voltage transformer
and/or power relays.
NOTE: Do not use a soldering iron or desoldering tool of more than 30 watts on
DPC contacts.
(B) With all the terminal pins cleaned and separated from DPC contacts, remove
the defective transformer/power relays and install new transformer/relays
making sure all terminal pins are inserted completely. Resolder all terminal
contacts carefully.
4. Fan motor
(A) Disconnect 2 lead wires from fan motor terminals.
(B) Remove 1 screw at located on oven attaching orifice assembly.
(C) Remove orifice assembly/Inverter power supply (U) from oven assembly.
(Refer page 15)
(D) Remove fan blade from the fan motor shaft by pulling it straight out.
(E) Remove 2 screws holding fan motor to orifice.
(F) Separate the fan motor from the orifice assembly by freeing 2 catch hooks on
the orifice assembly.
CAUTION
When replacing the magnetron, be sure the antenna
gasket is in place.
SCREW