Sharp R-4H55 Service Manual page 21

R-4H5.5
R-4X55
R-4X.558
TEST PROCEDURES
PROCEDURE
LETTER COMPONENT TEST
6-l. Touch SENSOR COOK pad and number 1 pad and 0 pad.
6-2. The control panel is in the sensor cooking operation.
6-3. After approximately 20 seconds, push plunger of select switch.This condition is same as
ludgement by AH sensor.
6-4. After approximately 3 seconds, cooking operation turns off, an audible signal will sound, and
the display will then revert to the time of day.
If the above is not the case, the control unit is probably defective.
If the above is proper, the AH sensor is probably defective.
Rl,R2:22ohm*1%1/2W
To
connector(F)
on Control Unit.
R3:1OkohmL5%1/4W
F-l -
R4: lMohmL5% l/4
F-2 -
F-3 -
CONNECTOR
r/ Plunger
18
NC
NO
FigureA. Sensor Dummy Resistor Circuit
P
WEIGHT SENSOR ASSEMBLY AND IC3lMEMORY) TEST.(R-4X!%,R-4X55B)
After replacing the weight sensor, turntable,control unit,turntable motor,or IC3, carry out the follow-
ing procedure in order to calibrate the weight sensor. If the weight sensor is not recalibrate, the food
may be over or under cooked.
The following procedure should be carried out with microwave oven in a fully assembled condition
(with outer case fitted).
1. Test Method
1. Place the turntable on the roller stay correctly, and close the door.
2. Plug the oven into a power point. ("88:88" will appear on the display.)
3. Press the STOP/CLEAR pad. (Display shows ' : " with sound of buzzer.)
4. Press the AUTO START/CLOCK pad. (Display shows '
5. Press the DEFROST SENSOR pad. (Display shows "
0" with sound of buzzer.)
6. Press the POWER LEVEL pad. (Display shows '
O".)
O".)
7. Press the INSTANT COOK/START pad. (Display shows " TEST" with sound of buzzer.)
8. Press the "4" of number pads. (Display shows "
lamps come on.)
4" with sound of buzzer, and tuntable and oven
9. After 56 seconds, make sure that the display shows "00055 - 00250" with sound of buzzer.
If display shows less than 00055 or more than 00250, weight sensor is defect.
10. Place the weight 1.3 Kg+1 % (water load 1.3 Kg+1 %) on the turntable.
11. Press the "6" of number pads. (Display shows "
oven lamps come on.)
6" with sound of buzzer, and turntable and
12. After 56 seconds, make sure that the display shows "00030 - 00200" with sound of buzzer.
If display shows less than 00030 or more than 00200, weight sensor is defect.
13. Disconnect the oven from power supply, and repeat above procedure items 1 to 7
14. Press the "7" of number pads, and make sure that the display shows "00030 -00200".
If display shows less than 00030 or more than 00200, IC3 is defect.
15. Press the STOP/CLEAR pad. (Display shows " : " with sound of buzzer.)
16. Impose 1.3 kg load on the defrosting rack and place it in the oven cavity. Touch the "DEFROST
SENSOR" pad. After approx. 56 seconds, time display appears.
2. Acceptance Standard.
1. Under 1.3 kg load : 32 min
22 sec. k 242 sec.
19