Sharp R-319FW Service Manual page 19

PROCEDURE
LETTER
clearing with a beep the key unit is faulty and must be replaced. If the control unit does not respond,
it is faulty and must be replaced. If a specific pad does not respond, the above method may be used
(after clearing the control unit) to determine if the control unit or key pad is at fault.
5. Reconnect all leads removed from components during testing.
6. Re-install the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
K RELAY 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.
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.
7. Remove the outer case and check voltage between Pin No. 1 of the 2 pin connector (A) and the normal
open terminal of the relay RY1 on the control unit with an A.C. voltmeter.
The meter should indicate 120 volts, if not check oven circuit.
RY1 and RY2 Relay Test
These relays are operated by D.C. voltage
Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation.
DC. voltage indicated ............... Defective relay.
DC. voltage not indicated ......... Check diode which is connected to the relay coil. If diode is good,
RELAY SYMBOL
RY1
RY2
8. Disconnect the power supply cord, and then remove outer case.
9. Open the door and block it open.
10. Discharge high voltage capacitor.
11. Reconnect all leads removed from components during testing.
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.
TEST PROCEDURES
COMPONENT TEST
G 8 G 7 G 6
5 4 3
0 9 8
MINUTE CHICKEN
CLOCK
PLUS BREAST
FROZEN
STOP
ROLLS& BEVERAGE
CLEAR
MUFFINS
GROUND MEAT CUSTOM
(COMPU DEFROST ) HELP
control unit is defective.
OPERATIONAL VOLTAGE
Approx. 24.0V D.C.
Approx. 24.0V D.C.
17
G 5 G 4 G 3
CHICKEN
2 1
PIECES
STEAKS/
7 6
CHOPS
KITCHEN
START
TIMER
FRESH
POWER FRESH
ROLLS&
LEVEL VEGETABLES
MUFFINS
FROZEN REHEAT
ENTREES SENSOR
CONNECTED COMPONENTS
Oven lamp / Turntable motor / Cooling fan motor
Power transformer
R-319FW
G 2 G 1
BAKED
POPCORN
POTATOES
FROZEN
RICE
VEGETABLES
FISH/ GROUND MEAT
SEAFOOD (SENSOR COOK)