Sharp R-9320 Service Manual page 35

TEST PROCEDURES (CONT'D)
PROCEDURE
LETTER
COMPONENT TEST
D HIGH VOLTAGE CAPACITOR TEST
DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE TOUCHtNG
ANY
OVEN COMPONENTS OR WIRING.
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1 If the capacitor is open, no high voltage will be available to the magnetron. Disconnect input leads
1 and check for short or open between the terminals using an ohmmeter.
/ Checking with a high ohm scale, if the high voltage capacitor is normal, the meter will indicate
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continuity for a short time and should indicate an open circuit once the capacitor is charged. If the
1 above is not the case, check the capacitor with the ohmmeter to see if it is short circuited between
j the terminals. If it is short circuited, replace the capacitor.
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E
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UPPER LATCH SWITCH TEST
/ The upper latch switch can be checked with an ohmmeter. Isolate the switch and then connect the
meter leads to the common ICOM) and normally open (NO) terminals of the switch. The meter
I should indicate an open circuit with the door opened and e closed circuit with the door closed.
In case improper operation is indicated, make a necessary switch adjustment or replace the
1 defective switch.
/ See adjustment procedure on page 58.
! 1
/
F I
LOWER LATCH SWITCH TEST
Isolate the switch and connect the ohmmeter leads to the common (COM) and normally open (NO)
terminals of the switch. The meter should indicate an open circuit with the door opened and a
closed circuit with the door closed. When the meter leads connected to the common (COM) and
normally closed (NC) terminals of the switch, it should indicate a closed circuit with the door
opened and an open circuit with the door closed.
In case improper operation is indicated, make a necessary switch adjustment or replace the defective
switch.
See adjustment procedure on page 58.
G
MONITOR SWITCH TEST
Before performing this test, make sure that the Upper and Lower Latch Switches are operating pro-
perly refer to the Test procedure E and F.
Connect one ohmmeter lead to one of the fuse terminals, and the other lead to the power trans-
former terminal to which the white wire from the wiring harness is connected.
When the door is open, the meter should indicate a closed circuit.
When the monitor switch lever of the upper latch hook is pushed by the screw-driver through the
upper latch hole on the front plate of the oven cavity with the door opened, in this condition the
plunger of the monitor switch is pushed in, the meter should indicate an open circuit.
ln case improper operation is indicated, replace the defective switch.
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