LG MA-972xx Service Manual
MICROWAVE OVEN
SER VICE MANUAL
CAUTION
BEFORE SERVICING THE UNIT, READ THE
SAFETY PRECAUTIONS IN THIS MANUAL.
MODEL: MA-972M
MA-972MW
SAFETY PRECAUTIONS
This device is to be serviced only by properly qualified service personnel.
Consult the service manual for proper service procedures to assure continued safety operation and for precautions to be
taken to avoid possible exposure to excessive microwave energy.
PRECAUTIONS TO BE OBSERVED BEFORE
AND DURING SERVICING TO AVOID
POSSIBLE EXPOSURE TO EXCESSIVE
MICROWAVE ENERGY
A) Do not operate or allow the oven to be operated with the door open.
B) Make the following safety checks on all ovens to be serviced before activating the magnetron or other
microwave source, and make repairs as necessary; (1) Interlock operation, (2) proper door closing, (3)
seal and sealing surfaces (arcing, wear, and other damage), (4) damage to or loosening of hinges and
latches, (5) evidence of dropping or abuse.
C) Before turning on microwave power for any service test or inspection within the microwave generating
compartments, check the magnetron, wave guide or transmission line, and cavity for proper alignment,
integrity, and connections.
D) Any defective or misadjusted components in the interlock, monitor, door seal, and microwave generation
and transmission systems shall be repaired, replaced, or adjusted by procedures described in this manual
before the oven is released to the owner.
E) A microwave leakage check to verify compliance with the Federal Performance Standard should be
performed on each oven prior to release to the owner.
TABLE OF CONTENTS
(Page)
SAFETY PRECAUTIONS
-----------------------------------------------------------------------------------
Inside front cover
SPECIFICATIONS
------------------------------------------------------------------------------------------------------------------
1-1
CAUTIONS
----------------------------------------------------------------------------------------------------------------------------
2-1
INSTALLATIONS
-------------------------------------------------------------------------------------------------------------------
3-1
OPERATING INSTRUCTIONS
-------------------------------------------------------------------------------------------------
4-1
FEATURES
-----------------------------------------------------------------------------------------------------------------------
4-1
CONTROL PANEL
-------------------------------------------------------------------------------------------------------------
4-1
OPERATING SEQUENCE
---------------------------------------------------------------------------------------------------
4-2
SCHEMATIC DIAGRAM
------------------------------------------------------------------------------------------------------
4-3
CIRCUIT DESCRIPTION
-----------------------------------------------------------------------------------------------------
4-4
SERVICE INFORMATION
-------------------------------------------------------------------------------------------------------
5-1
TOOLS AND MEASURING INSTRUMENTS
--------------------------------------------------------------------------
5-1
MICROWAVE LEAKAGE TEST
--------------------------------------------------------------------------------------------
5-1
MEASUREMENT OF MICROWAVE POWER OUTPUT
-----------------------------------------------------------
5-3
DISASSEMBLY AND ADJUSTMENT
------------------------------------------------------------------------------------
5-3
INTERLOCK CONTINUITY TEST
-----------------------------------------------------------------------------------------
5-7
COMPONENT TEST PROCEDURE
--------------------------------------------------------------------------------------
5-8
TROUBLE SHOOTING
-----------------------------------------------------------------------------------------------------
5-11
EXPLODED VIEW
------------------------------------------------------------------------------------------------------------------
6-1
REPLACEMENT PARTS LIST
-------------------------------------------------------------------------------------------------
7-1
SCHEMATIC DIAGRAM OF P.C.B.
-------------------------------------------------------------------------------------------
8-1
PRINTED CIRCUIT BOARD
------------------------------------------------------------------------------------------------
8-2
P.C.B. PARTS LIST
----------------------------------------------------------------------------------------------------------------
9-1
Loading...