7-19
NOTE: A MICROWAVE ENERGY LEAKAGE TEST MUST ALWAYS BE PERFORMED WHEN THE UNIT IS
SERVICED FOR ANY REASON.
(3) CHECKOUT PROCEDURES FOR CIRCUIT
BOARD
The following symptoms indicate a defective circuit
board.
1) Check the input current. If the input current is more
than 20A, check the magnetron and wiring. If the
input current is less than 0.5 A, there is no input to
the inverter.
2) The start function fails to operate but the high
voltage Systems, the interlock switches, the door
sensing and the relay check good.
3) The unit with a normal relay continuously operates.
4) The buzzer does not sound or continues to sound.
5) Some segments of one or more digits do not light
up, or they continue to light up, or segments light
when they should not.
6) Wrong figures appear.
7) The figures of all digits.
8) The clock does not keep time properly.
Summary of Contents for 721. 63762
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 1001 W171 W171 2016 2009 2007 2017 EV...
Page 38: ...2004 2008 2002 2006 W106 2381 8 3 CONTROLLER PARTS II EV...
Page 40: ...8 5 LATCH BOARD PARTS 4000 W102 4001 4002 4003 4002 4004 EV...
Page 44: ...8 21 SCHEMATIC DIAGRAM OF P C B...
Page 45: ...8 22 PRINTED CIRCUIT BOARD...
