LG LTM9000B, Service Manual

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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.
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.
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.
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 OR V-5230Q FOR PRIMARY SWITCH
TYPE NO. SZM-V 16-FA-62, VP-532A-OF OR V-5220Q FOR MONITOR SWITCH
TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF OR V-5230Q 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
Monitor
Switch
Secondary
Switch
NOTE : After checking for the continuity of switches, make sure that they are
connected correctly.
NO
COM
NC
COM
NO
COM
10. INTERLOCK CONTINUITY TEST