23
R-1750
R-1751
R-1752
R-1754
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
1) Disconnect the power supply cord, and then remove outer case.
2) Open the door and block it open.
3) To discharge high voltage capacitor, wait for 60 seconds.
4) Reconnect all leads removed from components during testing.
5) Re-install the outer case (cabinet).
6) Reconnect the power supply cord after the outer case is installed.
7) Run the oven and check all functions.
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon cable
is making good contact, verify that the stop switch operates properly; that is the contacts are closed
when the door is closed and open when the door is open. If the stop switch is good, disconnect the
flat ribbon cable that connects the key unit to the control unit and make sure the stop switch is closed
(either close the door or short the stop switch connector). Use the Key unit matrix indicated on the
control panel schematic and place a jumper wire between the pins that correspond to the STOP/
CLEAR pad making momentary contact. If the control unit responds by 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
KEY UNIT TEST
G 1
G 2
G 3
G14
G 5
G 6
G13
G12
G11
Baked
Potatoes
STOP/
CLEAR
MINUTE
PLUS
Keep
Warm
Popcorn
Reheat
Poultry
Meats
START
Set Up
Vegetables
Fish/
Seafood
Fan
Options
Light
Options
Pasta
Grains
Frozen
Food
Turntable
On/Off
Defrost
3+6
Beverage
Center
More from
Your
Microwave
6x6
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. To discharge high voltage capacitor. wait for 60 seconds.
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. 5 of the 4 pin connector (A) and the
common 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, RY2, RY3 and RY4 Relays 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, control unit is defective.
RELAY SYMBOL
OPERATIONAL VOLTAGE
CONNECTED COMPONENTS
RY1
Approx. 25.6V D.C.
Oven lamp / Stirrer motor / Cooling fan motor
RY2
Approx. 25.6V D.C.
Turntable motor
RY3
Approx. 25.6V D.C.
Hood motor
RY4
Approx. 25.6V D.C.
Hood motor (HIGH/LOW selection)
8. Disconnect power supply cord, and then remove outer case.
L
RELAY TEST
