Troubleshooting and Testing
3-10
Procedure
Letter
K
Component Test
Key Unit Test
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
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 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,
control
unit
is
defective.
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.
RELAY SYMBOL OPERATIONAL VOLTAGE CONNECTED COMPONENTS
RY1 Approx. 12.0V D.C. Oven lamp / Turntable motor / Cooling fan motor
RY2 Approx. 11.0V D.C.
Power transformer
Pin
NO. G1
Pin
NO. G13
Key unit ribbon cable
Key unit (Membrane Switch) front view
Summary of Contents for EI27MO45GSA
Page 2: ......
Page 32: ...Troubleshooting and Testing 3 14 Notes ...
Page 46: ...Wiring Diagrams 5 4 Notes ...
Page 52: ...Parts List 6 6 Notes ...