Sharp R-120DB, Service Manual

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15
R-120DB
R-120DK
R-120DR
R-120DW
(1) Place one cup of water in the center of the turntable tray in the oven cavity.
(2) Open the door, and touch COMPU COOK pad three times.
(3) Close the door, and then touch the "START" pad.
(4) The oven is in COMPU COOK condition.
(5) The oven will operate as follows. (in case of 1 piece of Rolls/muffins cooking)
1ST STAGE
LEVEL TIME
100% 15sec.
(6) If improper cooking time is indicated, the control unit is probably defective and should be checked.
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
12. Re-install the outer case (cabinet).
13. Reconnect the power supply cord after the outer case is installed.
14. Run the oven and check all functions.
L COMPU COOK TEST
To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary on
the PWB, this foil pattern acts as a fuse.
1. Foil pattern check and repairs.
1) Disconnect the power supply cord and then remove outer case.
2) Open the door and block it open.
3) Discharge high voltage capacitor.
4) Follow the troubleshooting guide given below for repair.
STEPS OCCURRENCE CAUSE OR CORRECTION
1 Only pattern at "a" is broken. *Insert jumper wire J1 and solder.
2 Pattern at "a" and "b" are broken. *Insert the coil RCILF2003YAZZ between "c" and "d".
5) Make a visual inspection of the varistor.
Check for burned damage and examine
the transformer with a tester for the
presence of layer short-circuit (check
the primary coil resistance which is
approximately 563
Ω ±
10%). If any
abnormal condition is detected, replace
the control unit.
6) Reconnect all leads removed from components during testing.
7) Re-install the outer case (cabinet).
8) Reconnect the power supply cord after the outer case is installed.
9) Run the oven and check all functions.
2. Follow the troubleshooting guide given below, if indicator does not light up after above check and
repairs are finished.
1) Disconnect the power supply cord and then remove outer case.
2) Open the door and block it open.
3) Discharge high voltage capacitor.
4) Disconnect the leads to the primary of the power transformer.
5) Ensure that these leads remain isolated from other components and oven chassis by using
insulation tape.
6) After that procedure, re-connect the power supply cord.
M FOIL PATTERN ON THE PRINTED WIRING BOARD TEST
Q10
1
T1
7
RY2
(J1)
(C10)
B
a
b
d
c
VRS1
D21