(TROUBLE 3) No microwave oscillation even though fan motor rotates.
CONDITION
No
microwave oscillation
CHECK
Check continuity of high
voltage capacitor terminals
with wires removed
Check continuity of high voltage 
rectifier in forward and backward
direction with DC megger
Connect megger leads to magnetron terminal and magnetron body
RESULT
Continuity
Continuity in backward direction
Continuity
CAUSE
Defective high
voltage
transformer
Defective high voltage rectifier
Defective
magnetron
REMEDY
Replace
Replace
Replace
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Check resistance of primary and |
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secondary coil of high voltage |
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transformer |
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| No |
Check continuity of magnetron |
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| Continuity | ||
with wires removed |
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| No |
Check continuity of filament |
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| Continuity | ||
terminal of high voltage |
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transformer |
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| 0 V |
Check D.C. voltage being |
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supplied to RELAY (RY1) coil |
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| Approx |
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| 15 VDC |
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Defective high
voltage
transformer
Defective
magnetron
Defective high
voltage
transformer
Defective touch
control circuit
Faulty
contacts or
RELAY (RY1)
or open
relay coil
Replace
Replace
Replace
Replace
Replace
21
