R-204(W)
9
When troubleshooting the microwave oven, it is helpful to
follow the Sequence of Operation in performing the checks.
Many of the possible causes of trouble will require that a
specific test be performed. These tests are given a proce-
dure letter which will be found in the “Test Procedure”
section.
IMPORTANT: If the oven becomes inoperative because
of a blown fuse F1. Check the ist. interlock
switch (SW1), monitor switch(SW2) and
2nd. interlock relay (RY2) before replac-
ing the F1 fuse.
TROUBLESHOOTING GUIDE
CONDITION
PROBLEM
A
B
C
D
E
E E
F G
H
I
I
J
K
L
L
M
Home fuse blows when power cord
is plugged into wall outlet.
Fuse F8A blows when power cord
is plugged into wall outlet. (Timer
off)
Oven does not operate at all.
Timer is not set but when door
closed, oven starts operation.
Oven does not start when timer
knob is turned, door closed.
Oven lamp does not light, when in
operation.
Fan motor does not operate.
Turntable motor assembly does
not operate.
Oven or electrical parts does not
stop when timer knob is at "0".
Oven seems to be operating but
little or no heat is produced in oven
load. (Microwave power level is set
at 800W.)
Oven does not operate properly during
the variable cooking condition except
800w cooking condition.
Oven goes into cook cycle but
shuts down before end of cooking
cycle.
Oven stops as soon as the oven is
started.
Fan motor, oven lamp and
turntable motor do not operate at
the same time.
OFF
CONDITION
COOKING
CONDITION
TEST PROCEDURE
POSSIBLE CAUSE
AND
DEFECTIVE PARTS
MAGNETRON
HIGH VOLTAGE TRANSFORMER
H.V. RECTIFIER
HIGH VOLTAGE CAPACITOR
1ST. INTERLOCK SWITCH (SW1)
2ND. INTERLOCK RELAY CONTROL SWITCH (SW3)
MONITOR SWITCH (SW2)
TEMPERATURE FUSE 120
˚C
FUSE F1
NOISE FILTER
FAN MOTOR
TURNTABLE MOTOR
POWER SUPPLY CORD
OVEN LAMP
SHORTED WIRE HARNESS
OPENED WIRE HARNESS
MIS-ADJUSTMENT SWITCHES
NO POWER AT WALL OUTLET
HIGH VOLTAGE FUSE
CONTROL UNIT
RELAY RY1
RELAY RY2
FOIL PATTERN ON P.W.B.
