I: Fuse 12A (1) (2) Test; J: Temperature Fuse Test; K: Magnetron Thermistor Test; L: Exhaust Thermistor Test - Sharp R-CD1200M Service Manual

[9] I: FUSE 12A (1) (2) TEST

1. Disconnect the power supply cord, and then remove outer case and rear cabinet.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. If the fuse is blown, check the magnetron, high voltage capacitor, high voltage rectifier assembly, according to the "TEST PROCEDURE" before
replacing the blown fuse. Then replace the fuse.
5. Reconnect all leads removed from components during testing.
6. Reinstall the rear cover and the outer case (cabinet).
7. Reconnect the power supply cord after the rear cover and the outer case are installed.
8. Run the oven and check all functions.

[10] J: TEMPERATURE FUSE TEST

1. Disconnect the power supply cord, and then remove outer case and rear cabinet.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. A continuity check across the temperature fuse terminals should indicate a closed circuit unless the temperature of the temperature fuse reaches
specified temperature as shown below.
Open temperature
Magnetron temperature
fuse (1)
Magnetron temperature
fuse (2)
Magnetron temperature
fuse (1), (2)
Oven temperature fuse
5. Reconnect all leads removed from components during testing.
6. Reinstall the rear cover and the outer case (cabinet).
7. Reconnect the power supply cord after the rear cover and the outer case are installed.
8. Run the oven and check all functions.
CAUTION: IF THE TEMPERATURE FUSE INDICATES AN OPEN CIRCUIT AT ROOM TEMPERATURE, REPLACE TEMPERATURE FUSE.

[11] K: MAGNETRON THERMISTOR TEST

1. Disconnect the power supply cord, and then remove outer case and rear cabinet.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect the connector of the magnetron thermistor from the harness. Measure the resistance of the thermistor with an ohmmeter. Connect the
ohmmeter leads to the connector of the thermistor.
Room temperature
68°F (20°C)
If the meter does not indicate above resistance, replace the thermistor.
5. Reconnect all leads removed from components during testing.
6. Reinstall the rear cover and the outer case (cabinet).
7. Reconnect the power supply cord after the rear cover and the outer case are installed.
8. Run the oven and check all functions.

[12] L: EXHAUST THERMISTOR TEST

The exhaust thermistor can be checked by using the Special function (SF-6). Check the exhaust thermistor, referring to the pages of the Exhaust ther-
mistor check (SF-6).
If the display shows "OH", the exhaust thermistor is normal. If the display shows "no", the exhaust thermistor is abnormal and it should be replaced.
Close temperature
150°C Non resetable type
120°C Non resetable type
Resistance
Approx. 750KΩ
Display or
Condition
Magnetron (1) Failure:
EE1
Test magnetron (1) and fan motor.
Magnetron (2) Failure:
EE2
Test magnetron (2) and fan motor.
Magnetron (1), (2) Failure: Test magnetron (1), (2).
EE3
Check fan motor and ventilation opening.
Food has been burned in oven.
Oven shut off
Temperature of oven inside is very high.
7 – 4
RCD1200M
Check point