(TROUBLE 3) No microwave oscillation even though fan motor rotates.
CONDITION |
| CHECK |
| RESULT |
| CAUSE |
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No | Check continuity of high | No |
microwave | voltage fuse | Continuity |
oscillation |
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| Replace high voltage fuse |
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REMEDY
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| Continuity |
Check continuity if high |
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voltage capacitor terminals |
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with wires removed |
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Check continuity of high voltage |
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| Continuity in |
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| ||
rectifier in forward and backward |
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| backward | |
direction with DC megger |
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| direction | |
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| Continuity |
Connect megger leads to |
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magnetron terminal and |
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magnetron body |
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| 0 Ω or ∞ |
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 high voltage rectifier
Defective
magnetron
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
Replace
Replace
Replace
47
