Sharp R-402FW, Service Manual

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10
R - 402FW
R - 4 0 4 F K
A MAGNETRON ASSEMBLY TEST
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
Home fuse or circuit breaker blows
when power cord is plugged into wall
receptacle
C/T fuse blows when power cord is
plugged into wall receptacle.
All letters and indicators do not ap-
pear in display when power cord is
first plugged into wall outlet.
Display does not operate properly
when STOP/CLEAR key is touched.
(Buzzer should sound and ":" or time
of day should appear in display.)
Oven lamp does not light when door
is opened.
Oven lamp does not go out when
door is closed.
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 P-
50 mode. (Operates properly on
Cooking P-HI (HIGH) mode.)
Oven goes into COMPU DEFROST
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 CAVITY TEMPERATURE FUSE C/T FUSE SECONDARY INTERLOCK SYSTEM PRIMARY INTERLOCK SWITCH MONITOR SWITCH C/T FUSE OVEN LAMP OR SOCKET COOLING FAN MOTOR TURNTABLE MOTOR TOUCH CONTROL PANEL WRONG OPERATION LOW VOLTAGE DIRTY OVEN CAVITY KEY UNIT RELAY (RY1) COMPU DEFROST FOIL PATTERN ON PWB.
POSSIBLE CAUSE
AND
DEFECTIVE PARTS
TEST PROCEDURE
RE RE A B C D E E F F G H RE RE CK I CK CK CK J K L M
COOKING
CONDITION
CK = Check / RE = Replace