Electrolux EI24MO45IBA Technical & Service Manual page 27

Procedure
Letter
KEY UNIT TEST
J
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. Isolate the key unit with the control panel frame to be tested.
5. Using an ohmmeter and referring to the key unit matrix indicated on the control unit circuit,
check the circuit between the pins of the key unit that correspond to the STOP/CLEAR pad.
When the pad is pressed, the ohmmeter should indicate short circuit. When the pad is released,
the ohmmeter should indicate open circuit. If incorrect readings are obtained, the key unit is
faulty and must be replaced. About the other pads, the above method may be used
6. Reconnect all leads removed from components during testing.
7. Re-install the outer case (cabinet).
8. Reconnect the power supply cord after the outer case is installed.
9. Run the oven and check all functions.
K RELAY TEST
1. Disconnect power supply cord, and 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 240 volts, if not check oven circuit.
Shut-off, Cook and Heater 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,
Troubleshooting and Testing
Component Test
control unit is defective.
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