LG MB-4322A Service Manual ▷ View online
5-14
(TROUBLE 3) Output power is low.
CONDITION
CHECK
RESULT
CAUSE
REMEDY
Output is low
Lower than 207V.
Normal
Less than 8.5
o
C.
Measure the
magnetron’s
output(See test
procedure).
magnetron’s
output(See test
procedure).
Faulty magnetron.
Replace.
Decrease in power
source voltage
with load.
source voltage
with load.
Suggest customer
contact local
electric power
utility co. or
qualified
electrician.
contact local
electric power
utility co. or
qualified
electrician.
Check the
power source
voltage
oscillating.
power source
voltage
oscillating.
No continuity.
No continuity.
replace.
Malfunction of the
timer switch.
timer switch.
Faulty thermostat.
replace.
Check the
continuity of the
timer switch
contacts.
continuity of the
timer switch
contacts.
Check the
continuity of the
thermostat.
continuity of the
thermostat.
CONDITION
CHECK
RESULT
CAUSE
REMEDY
(TROUBLE 4) Grill.
CONDITION
CHECK
RESULT
CAUSE
REMEDY
1. Heater is not
operating.
Abnormal.
Normal.
Normal.
Heater.
Thermostat
(Grill)
(Grill)
Abnormal.
Malfunction the
thermostat.
thermostat.
Malfunction the
heater.
heater.
Replace.
Wire connection.
No continuity.
Open or loosen.
Replace.
Replace.
5-15
CONDITION
CHECK
RESULT
CAUSE
REMEDY
No microwave
oscillation.
oscillation.
No continuity.
Continuity.
Abnormal or burn
out.
out.
Defective monitor
resistor.
resistor.
Replace.
Malfunction of the
power control
switch.
power control
switch.
Replace the power
control switch.
control switch.
Check the
power control
switch(cooking
state).
power control
switch(cooking
state).
Check the
monitor resistor.
monitor resistor.
Abnormal
Defective AC
relay.
relay.
Replace.
Normal
Check the AC
relay.
relay.
Abnormal
Open the
secondary winding
of the high voltage
transformer of
faulty insulation of
filament winding.
secondary winding
of the high voltage
transformer of
faulty insulation of
filament winding.
Replace .
Check H.V.
transformer.
transformer.
Abnormal
Shorted H.V. diode
Replace .
Check H.V.
diode.
diode.
Abnormal
Faulty capacitor.
Replace .
Check H.V.
capacitor.
capacitor.
Abnormal
Faulty magnetron.
Replace .
Magnetron
(TROUBLE 5) Oven does not cook at all even though turntable rotates.
DOOR PARTS
LATCH BOARD PARTS
CONTROL PANEL PARTS
INTERIOR PARTS
BASE PLATE PARTS
OVEN CAVITY PARTS
6-1
EXPLODED VIEW
INTRODUCTION
6-2
13581A
14970A
14026A
13552A
13536A
15006A
13213A
13720D
13352A
DOOR PARTS
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