R-4G75M (serv.man4). Section 3 Component replacement and adjustment procedure, MWO measurement (page 23-29) - Sharp Home Appliance Service Manual (repair manual). Page 4

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where the monitor switch and 2nd latch switch have
activated with the door closed. The vertical position of the
latch hook should be placed where the primary latch
switch and stop switch have activated with the door
closed.

4. Secure the screws with washers firmly.
5. Make sure of the primary, 2nd latch switch, stop switch

and monitor switch operation. If those switches have not
activated with the door closed, two (2) screws holding
latch hook to oven cavity front flange and adjust the latch
hook position.

After adjustment, make sure of following:
1. In and out play of door remains less than 0.5 mm when

latched position. First check latch hook position, pushing
and pulling the door toward the oven face. The results
(play of the door) should be less than 0.5 mm.

2. The contacts (COM - NO) of primary latch switch and stop

switch interrupt the circuit before the door can be opened.

3. The contacts (COM - NC) of the monitor switch close

when the door is opened.

4. The contacts (COM - NO) of the 2nd latch switch open

when the door is opened.

5. Re-install outer case and check for microwave leakage

around the door with an approved microwave survey
meter. (Refer to Microwave Measurement Procedure.)

Remove the door assembly, referring to from item 1 through
item 4 of “DOOR REPLACEMENT”.
1. Place the door assembly on a soft cloth with facing up.
2. Remove the choke cover, referring to “CHOKE COVER

REMOVAL”.

3. Remove the four (4) screws holding the door frame to the

door panel assembly.

4. Release the door frame from the door panel assembly,

now the door frame is free.

5. Gently lever the door screen from the door frame, taking

care not to scratch the door screen.

6. Replace tape and secure frame screen.

DOOR REPLACEMENT
1. CARRY OUT 3D CHECKS
2. Remove five (5) screws holding the upper and lower oven

hinge to the oven cavity. The lower oven hinge is now
free.

3. Remove door assembly with upper oven hinge by pulling

it forward.

4. Separate the door assembly and upper oven hinge. Door

assembly is now free.

5. Re-install upper oven hinge to the new door assembly.
6. On re-installing new door assembly, secure the upper

and lower oven hinges with the five (5) mounting screws
to the oven cavity. Make sure the door is parallel with
bottom line of the oven face plate and the latch head pass
through the latch holes correctly.

7. CARRY OUT 4R CHECKS
Note:

After any service to the door, the approved microwave
survey meter should be used to assure in compliance
with proper microwave radiation standards. (Refer
to Microwave Measurement Procedure.)

DOOR ADJUSTMENT
When removing and/or loosening hinges such as in door
replacement, the following adjustment criteria are taken.
Door is adjusted to meet the following three conditions by
keeping screws of hinge loose.
1. Adjust door latch heads at a position where they smoothly

catch the latch hook through the latch holes. Refer to
latch switch adjustments.

2. Deviation of the door alignment from horizontal line of

cavity face plate is to be less than 1.0mm.

3. The door is positioned with its face depressed toward the

cavity face plate.

4. Reinstall outer case and check for microwave leakage

around the door with an approved microwave survey
meter. (Refer to Microwave Measurement Procedure.)

LATCH HEAD REMOVAL
1. Insert an iron plate(thickness of about 0.5mm)
2. Release the latch spring from the tabs of the door panel.
3. Release the latch spring from the latch head.
4. Release the latch head from the door panel.
5. Now, the latch head is free.