LG MS-190A Service Manual ▷ View online
H. LATCH BOARD ASSEMBLY AND
SUCTION GUIDE ASSEMBLY
NOTE: Suction Guide Main ASS’Y consists of Latch
Board ASS’Y and Suction Guide ASS’Y. To repair any of
them, should be removed first Suction Guide Main
ASS’Y.
Board ASS’Y and Suction Guide ASS’Y. To repair any of
them, should be removed first Suction Guide Main
ASS’Y.
1) Remove the screw.
2) Disconnect the leadwire.
5-6
Rotate right
and pull out
and pull out
Latch board ASS'Y
Connecting screw
I. FAN MOTOR ASSEMBLY REMOVAL
NOTE: Suction Guide Main ASS’Y consists of Latch
Board ASS’Y and Suction Guide ASS’Y. To repair any of
them, should be removed first Suction Guide Main
ASS’Y.
Board ASS’Y and Suction Guide ASS’Y. To repair any of
them, should be removed first Suction Guide Main
ASS’Y.
1) Disconnect the leadwire from fan motor.
2) Remove the fan.
3) Remove the two screws holding the fan motor
2) Remove the fan.
3) Remove the two screws holding the fan motor
assembly to the suction guide ass’y.
Fan Motor ASS'Y
Suction
Guide
Guide
J. HIGH VOLTAGE TRANSFORMER
REMOVAL
1) Discharge the high voltage capacitor.
2) Disconnect the leadwire from magnetron, high voltage
2) Disconnect the leadwire from magnetron, high voltage
transformer, and capacitor.
3) Remove the screw holding the high voltage
transformer to the baseplate.
Pull out suction guide Main ASS’Y
Remove the screw
K. HIGH VOLTAGE CAPACITOR AND
DIODE REMOVAL
1) Discharge the high voltage capacitor.
2) Disconnect the leadwire from the high voltage
2) Disconnect the leadwire from the high voltage
capacitor.
3) Remove the screw holding the high voltage capacitor
bracket (refer to high voltage transformer removal
on previous page, FIG.1).
L. REMOVING THE TURNTABLE MOTOR
1) Remove the turntable.
2) Remove the rotating ring ass’y by hand.
3) Remove the turntable motor cover.
3) Remove the turntable motor cover.
The turntable base cover is easily removed by
pinching the six parts with wire cutting pliers.
4) Disconnect the leadwire from the turntable motor
terminals.
5) Remove the screw securing the turntable motor to
the oven cavity assembly.
6) After repairing the motor, rotate the removed
turntable motor cover.
7) Fit the turntable motor cover's projecting part to the
base plate slit.
NOTE:
1. Remove the wire lead from the turntable motor
1. Remove the wire lead from the turntable motor
VERY CAREFULLY.
2. Be sure to grasp the connector, not the wires,
when removing.
5-7
Wire Leads
Turntable Motor
M. INTERLOCK SYSTEM
1) INTERLOCK MECHANISM
The door lock mechanism is a device which has
been specially designed to eliminate completely
microwave activity when the door is opened during
cooking and thus to prevent the danger resulting
from the microwave leakage.
been specially designed to eliminate completely
microwave activity when the door is opened during
cooking and thus to prevent the danger resulting
from the microwave leakage.
2) MOUNTING OF THE PRIMARY/MONITOR/
SECONDARY SWITCHES TO THE LATCH
BOARD
BOARD
PRIMARY
SWITCH
SWITCH
ADJUSTMENT
DIRECTION
DIRECTION
MONITOR
SWITCH
SWITCH
SECONDARY
SWITCH
SWITCH
3) INSTALLATION AND ADJUSTMENT OF THE
LATCH BOARD TO THE OVEN ASSEMBLY
• Mount the latch board to the oven assembly.
• Adjust the latch board in the arrow direction so that
• Adjust the latch board in the arrow direction so that
oven door will not have any play in it when the door
is closed.
is closed.
• Tighten the mounting screw.
• Check for play in the door by pushing the door
• Check for play in the door by pushing the door
release button. Door movement should be less
than 0.5 mm. (1/64 inch)
than 0.5 mm. (1/64 inch)
Don't push the door release button while making
adjustment. Make sure that the latch moves
smoothly after adjustment are completed and that
the screws are tight. Make sure the primary,
monitor, and secondary switches operate properly
by following the continuity test procedure.
smoothly after adjustment are completed and that
the screws are tight. Make sure the primary,
monitor, and secondary switches operate properly
by following the continuity test procedure.
* After repairing Turn Table Motor. Be sure to
remove all sharp edges around the motor cover,
and notify to customers to be careful.
and notify to customers to be careful.
CAUTION: CHECK THE CORRECT POSITION
MAGNETRON
H.V. TRANSFORMER
PRIMARY
CIRCUIT PROTECTOR
H.V. CAPACITOR
H.V.
DIODE
DIODE
FIG. 1
A. PRIMARY INTERLOCK SWITCH TEST
When the door release button is depressed slowly
with the door closed, an audible click should be
heard at the same time or successively at
intervals. When the button is released slowly, the
latches should activate the switches with an
audible click.
If the latches do not activate the switches when
the door is closed, the switches should be a
adjusted in accordance with the adjustment
procedure. Disconnect the wire lead from the
primary switch. Connect the ohmmeter leads to
the common (COM) and normally open (NO)
terminal of the switch. The meter should indicate
an open circuit in the door open condition.
When the door is closed, the meter should
indicate a closed circuit.
When the primary switch operation is abnormal,
make the necessary adjustment or replace the
switch only with the same type of switch.
with the door closed, an audible click should be
heard at the same time or successively at
intervals. When the button is released slowly, the
latches should activate the switches with an
audible click.
If the latches do not activate the switches when
the door is closed, the switches should be a
adjusted in accordance with the adjustment
procedure. Disconnect the wire lead from the
primary switch. Connect the ohmmeter leads to
the common (COM) and normally open (NO)
terminal of the switch. The meter should indicate
an open circuit in the door open condition.
When the door is closed, the meter should
indicate a closed circuit.
When the primary switch operation is abnormal,
make the necessary adjustment or replace the
switch only with the same type of switch.
B. SECONDARY INTERLOCK SWITCH TEST
Disconnect the wire lead from the secondary
switch.
Connect the ohmmeter leads to the common
(COM) and normally open (NO) terminals of the
switch. The meter should indicate a open circuit in
the door open condition. When the door is closed,
meter should indicate an closed circuit. When the
secondary switch operation is abnormal, make the
necessary adjustment or replace the switch only
with the same type of switch.
switch.
Connect the ohmmeter leads to the common
(COM) and normally open (NO) terminals of the
switch. The meter should indicate a open circuit in
the door open condition. When the door is closed,
meter should indicate an closed circuit. When the
secondary switch operation is abnormal, make the
necessary adjustment or replace the switch only
with the same type of switch.
C. MONITOR SWITCH TEST
Disconnect the wire lead from the monitor switch.
Connect the ohmmeter leads to the common
(COM) and normally closed (NC) terminals of the
switch. The meter should indicate closed circuit in
the door open condition. When the door is closed,
meter should indicate an open circuit. When the
monitor switch operation is abnormal, replace with
the same type of switch.
NOTE: After repairing the door or the interlock
system, it is necessary to do this continuity
test before operating the oven.
Connect the ohmmeter leads to the common
(COM) and normally closed (NC) terminals of the
switch. The meter should indicate closed circuit in
the door open condition. When the door is closed,
meter should indicate an open circuit. When the
monitor switch operation is abnormal, replace with
the same type of switch.
NOTE: After repairing the door or the interlock
system, it is necessary to do this continuity
test before operating the oven.
5-8
WARNING : FOR CONTINUED PROTECTION AGAINST EXCESSIVE RADIATION
EMISSION, REPLACE ONLY WITH IDENTICAL REPLACEMENT PARTS.
TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF FOR PRIMARY SWITCH
TYPE NO. SZM-V 16-FA-61 OR VP-531A-OF FOR MONITOR SWITCH
TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF FOR SECONDARY SWITCH
TYPE NO. SZM-V 16-FA-61 OR VP-531A-OF FOR MONITOR SWITCH
TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF FOR SECONDARY SWITCH
COMPONENTS
TEST PROCEDURE
RESULTS
SWITCHES
Check for continuity of the
Door
Door
(Wire leads removed)
switch with an Ohm-meter
open
closed
Primary
Switch
Switch
Monitor
Switch
Switch
NOTE : After checking for the continuity of switches, make sure that are
connected correctly.
NO
COM
NC
COM
NO
COM
NO
COM
INTERLOCK CONTINUITY TEST
Secondary
Switch
Switch
A. PRIMARY INTERLOCK SWITCH TEST
When the door release button is depressed slowly
with the door closed, an audible click should be
heard at the same time or successively at
intervals. When the button is released slowly, the
latches should activate the switches with an
audible click.
If the latches do not activate the switches when
the door is closed, the switches should be a
adjusted in accordance with the adjustment
procedure. Disconnect the wire lead from the
primary switch. Connect the ohmmeter leads to
the common (COM) and normally open (NO)
terminal of the switch. The meter should indicate
an open circuit in the door open condition.
When the door is closed, the meter should
indicate a closed circuit.
When the primary switch operation is abnormal,
make the necessary adjustment or replace the
switch only with the same type of switch.
with the door closed, an audible click should be
heard at the same time or successively at
intervals. When the button is released slowly, the
latches should activate the switches with an
audible click.
If the latches do not activate the switches when
the door is closed, the switches should be a
adjusted in accordance with the adjustment
procedure. Disconnect the wire lead from the
primary switch. Connect the ohmmeter leads to
the common (COM) and normally open (NO)
terminal of the switch. The meter should indicate
an open circuit in the door open condition.
When the door is closed, the meter should
indicate a closed circuit.
When the primary switch operation is abnormal,
make the necessary adjustment or replace the
switch only with the same type of switch.
B. SECONDARY INTERLOCK SWITCH TEST
Disconnect the wire lead from the secondary
switch.
Connect the ohmmeter leads to the common
(COM) and normally open (NO) terminals of the
switch. The meter should indicate a open circuit in
the door open condition. When the door is closed,
meter should indicate an closed circuit. When the
secondary switch operation is abnormal, make the
necessary adjustment or replace the switch only
with the same type of switch.
switch.
Connect the ohmmeter leads to the common
(COM) and normally open (NO) terminals of the
switch. The meter should indicate a open circuit in
the door open condition. When the door is closed,
meter should indicate an closed circuit. When the
secondary switch operation is abnormal, make the
necessary adjustment or replace the switch only
with the same type of switch.
C. MONITOR SWITCH TEST
Disconnect the wire lead from the monitor switch.
Connect the ohmmeter leads to the common
(COM) and normally closed (NC) terminals of the
switch. The meter should indicate closed circuit in
the door open condition. When the door is closed,
meter should indicate an open circuit. When the
monitor switch operation is abnormal, replace with
the same type of switch.
NOTE: After repairing the door or the interlock
system, it is necessary to do this continuity
test before operating the oven.
Connect the ohmmeter leads to the common
(COM) and normally closed (NC) terminals of the
switch. The meter should indicate closed circuit in
the door open condition. When the door is closed,
meter should indicate an open circuit. When the
monitor switch operation is abnormal, replace with
the same type of switch.
NOTE: After repairing the door or the interlock
system, it is necessary to do this continuity
test before operating the oven.
5-8
WARNING : FOR CONTINUED PROTECTION AGAINST EXCESSIVE RADIATION
EMISSION, REPLACE ONLY WITH IDENTICAL REPLACEMENT PARTS.
TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF FOR PRIMARY SWITCH
TYPE NO. SZM-V 16-FA-61 OR VP-531A-OF FOR MONITOR SWITCH
TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF FOR SECONDARY SWITCH
TYPE NO. SZM-V 16-FA-61 OR VP-531A-OF FOR MONITOR SWITCH
TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF FOR SECONDARY SWITCH
COMPONENTS
TEST PROCEDURE
RESULTS
SWITCHES
Check for continuity of the
Door
Door
(Wire leads removed)
switch with an Ohm-meter
open
closed
Primary
Switch
Switch
Monitor
Switch
Switch
NOTE : After checking for the continuity of switches, make sure that are
connected correctly.
NO
COM
NC
COM
NO
COM
NO
COM
INTERLOCK CONTINUITY TEST
Secondary
Switch
Switch