9
R-312AW
R-312AK
TROUBLESHOOTING GUIDE
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 procedure letter which
will be found in the "Test Procedure"section.
IMPORTANT: If the oven becomes inoperative because of a blown monitor fuse in the monitor switch and primary interlock
switch circuit, check the monitor switch and primary interlock switch before replacing the monitor fuse. If
monitor fuse is replaced, the mintor switch should be replaced at the same time.
CK = Check / RE = Replace
Home fuse or circuit breaker
blows when power cord is plugged
into wall receptacle
Monitor fuse blows when power
cord is plugged into wall recepta-
cle.
All letters and indicators do not
appear in display when power cord
is first plugged into wall outlet.
Display does not operate prop-
erly when STOP/CLEAR key is
touched. (Buzzer should sound
and ":" or time of day should ap-
pear in display.)
Oven lamp does not light when
door is opened.
Oven lamp does not go out when
door is closed.
Oven lamp does not light in cook-
ing cycle. (Lights when door is
opened.)
Oven lamp does not light at all.
Oven lamp lights but fan motor and
turntable motor do not operate.
Oven does not go into cook cycle
when START pad is touched
Oven seems to be operating but
little or no heat is produced in
oven load. (Food incompletely
cooked or not cooked at all at end
of cook cycle.)
Oven goes into a cook cycle but
extremely uneven heating is pro-
duced in oven load (food).
Oven does not cook properly
when programmed for Cooking
Power 5 mode. (Operates prop-
erly on Cooking Power 10 (HIGH)
mode.)
Oven goes into COMPU DE-
FROST but food is not defrosted
well.
OFF
CONDITION
PROBLEM
CONDITION
SHORT IN POWER CORD
SHORT OR OPENED WIRING
MAGNETRON
POWER TRANSFORMER
H.V. RECTIFIER ASSEMBLY
HIGH VOLTAGE CAPACITOR
THERMAL CUT-OUT
SECONDARY INTERLOCK SYSTEM
PRIMARY INTERLOCK SWITCH
MONITOR SWITCH
MONITOR FUSE
OVEN LAMP OR SOCKET
COOLING FAN MOTOR
TURNTABLE MOTOR
TOUCH CONTROL PANEL
WRONG OPERATION
LOW VOLTAGE
DIRTY OVEN CAVITY
RELAY (RY1)
KEY UNIT
COMPU DEFROST
FOIL PATTERN ON PWB.
NOISE FILTER
POSSIBLE CAUSE
AND
DEFECTIVE PARTS
TEST PROCEDURE
RE RE A B C D E F F G H RE RE CK J CKCK CK L K M N
I
COOKING
CONDITION
