Sharp KB-6024MS Service Manual page 13

PROCEDURE
LETTER
2. Re-install the outer case (cabinet).
3. Reconnect the power supply cord after the outer case is installed.
4. Run the oven and check all function.
D DEFROST TEST
WARNING : The oven should be fully assembled before following procedure.
() Place one cup of water in the center of the tray in the oven cavity.
(2) Close the drawer, touch the Defrost pad. Then select Steaks/Chops by touching the number pad
2. And touch the number pad 5. (Now, weight 0.5lb is set.) And then touch the start pad.
(3) The oven is in Defrost cooking condition.
(4) The oven will operate as follows
(5) If improper operation is indicated, the control unit is probably defective and should be checked.
E PROCEDURES TO BE TAKEN WHEN THE FUSE ON THE PRINTED WIRING BOARD (PWB) IS OPEN.
To protect the electronic circuits, this model is provided with a fuse added to the primary on the
PWB.
. Fuse check and repairs.
) Disconnect the power supply cord.
2) Remove the outer case cabinet.
3) Open the door and block it open.
4) Discharge high voltage capacitor.
5) If the Fuse is blown, replace power unit.
6) Make a visual inspection of the varistor. Check for burned damage. If the varistor has been
burned, replace the power unit.
7) Examine the touch control transformer with a tester for the presence of layer short-circuit (check
the primary coil resistance which is approximately 5.6Ω ± 0%). If any abnormal condition is
detected, replace the touch control transformer.
8) Reconnect all leads removed from components during testing.
9) Re-install the outer case (cabinet).
0) Reconnect the power supply cord after the outer case is installed.
) 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.
) Disconnect the power supply cord.
2) Remove the outer case cabinet.
3) Open the door and block it open.
4) Discharge high voltage capacitor.
5) Disconnect the leads to the primary of the power transformer.
6) Ensure that these leads remain isolated from other components and oven chassis by using
insulation tape.
7) After that procedure, re-connect the power supply cord.
8) Follow the troubleshooting guide given below for repair.
STEPS

2
.
TEST PROCEDURES
WEIGHT ST STAGE
LEVEL TIME
0.5lb 60% 20sec.
OCCURRENCE
The rated AC voltage is not present between
Pin Nos. 5 and 7 of the 4-pin connecter (CN-A).
The rated AC voltage is present at primary
side of touch control transformer.
COMPONENT TEST
2ND STAGE 3RD. STAGE
LEVEL TIME LEVEL
40% 20sec. 30%
CAUSE OR CORRECTION
Check supply voltage and oven power cord.
Touch control transformer or secondary circuit defective.
Check and replace touch control transformer or power unit
3
KB-6024MS
KB-6024MK
KB-6024MW
TIME
45sec.