Daewoo KOC-960P0A - Page 32

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(TROUBLE 3) No microwave oscillation even though fan motor rotates.
Condition Check Result Cause
Defective high
voltage transformer
Remedy
No microwave
oscillation
Check continuity of
high voltage fuse
Check continuity of
high voltage capacitor
terminals with wires
removed
Continuity
Replace
Replace high voltage fuse
Defective high
voltage rectifier
Check continuity of
high voltage rectifier
in forward and
backward direction
with DC megger
Continuity
in backward
direction
Replace
Defective
magnetron
Connect megger
leads to magnetron
terminal and
magnetron body
Continuity
Replace
Defective high
voltage transformer
Check resistance of
primary and
secondary coil of high
voltage transformer
0 Ω or ∞
Replace
Defective
magnetron
Check continuity of
magnetron heater
with wires removed
No
Continuity
Replace
Defective high
voltage transformer
Check continuity of
filament terminal of
high voltage
transformer
No
Continuity
No
Continuity
Replace
Defective timer
ass’y
Check continuity of
microwave select
switch
Replace
Defective touch
control circuit
Check D.C. voltage
being supplied to
RELAY (RY6) coil
0V
Replace
Faulty contacts or
RELAY (RY6) or
open relay coil
Approx.
15VDC
Replace
No
Continuity