7-14
TEST AND CHECKOUT PRECEDURES AND TROUBLESHOOTING
CAUTIONS
1. DISCONNECT THE POWER SUPPLY CORD FROM THE OUTLET WHENEVER REMOVING THE OUTER CASE
FROM THE UNIT. PROCEED WITH THE TEST ONLY AFTER DISCHARGING THE HIGH VOLTAGE CAPACITOR
AND REMOVING THE LEAD WIRES FROM THE INVERTER MODULE.
2. ALL OPERATIONAL CHECKS WITH MICROWAVE ENERGY MUST BE DONE WITH A LOAD (1 LITER OF
WATER IN CONTAINER) IN THE OVEN.
COMPONENTS
TEST PROCEDURE
RESULTS
INVERTER
(Lead wires removed)
MAGNETRON
(Lead wires removed)
Note: Do not try to repair the inverter board, nor try
to make any adjustments to the board.
Check wiring to the inverter:
1. Unplug the oven’s main power supply.
2. Visually inspect 4 connectors on the inverter
board: CN701, CN702, CN703, E701 to see
whether there are any signs of failure due to
loose wires, bad crimping, sign of overheating,
etc.
1. Measure the resistance.
(Ohm-meter scale: Rx1)
• Filament terminal
2. Measure the resistance.
(Ohm-meter scale: Rx1000)
• Filament to chassis
Normal: Less than 1 ohm
Normal: Infinite
CN702
CN703
E701
CN701
120V AC
Heat Sink
Control Signal
In/Out
High Voltage
Output to
Magnetron
A. TEST PROCEDURES
Summary of Contents for LMVM1945SB
Page 9: ...5 1 SCHEMATIC DIAGRAM OVERALL CIRCUIT DIAGRAM ...
Page 10: ...5 2 MATRIX CIRCUIT FOR TOUCH KEY BOARD ...
Page 37: ...8 2 CONTROLLER PARTS I 23506A 268711 ...
Page 38: ...8 3 CONTROLLER PARTS II 268712 WTT028 250201 23572A 24810P 24781M ...
Page 40: ...8 5 LATCH BOARD PARTS 43500A WSZ085 43501A 466001 466003 466001 44510A ...
Page 44: ...8 17 SCHEMATIC DIAGRAM OF P C B ...
Page 45: ...8 18 PRINTED CIRCUIT BOARD ...
