Chapter 6. Troubleshooting Guide - Sharp R-CD1200M Service Manual

RCD1200M
CHAPTER 6.
RCD1200M
TROUBLESHOOTING GUIDE
Service Manual
Never touch any part in the circuit with your hand or an uninsulated tool while the power supply is connected.
When troubleshooting the microwave oven, it is helpful to follow the Sequence of Operation in performing the checks. Many of the possible causes of
trouble will require that a specific test be performed. These tests are given a procedure letter which will be found in the "Test Procedure" section.
IMPORTANT:
If the oven becomes inoperative because of a blown monitor fuse, check the monitor switches (1), (2), primary interlock relay RY1, door sensing
switch and secondary interlock switches (1), (2), before replacing the monitor fuse. If monitor fuse is replaced, the monitor switch (1) and/or (2) must
also be replaced. Use part FFSBA033WRKZ as an assembly.
IMPORTANT:
Whenever troubleshooting is performed with the power supply cord disconnected. It may, in some cases, be necessary to connect the power supply
cord after the outer case has been removed, in this event,
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge two high voltage capacitors.
4. Disconnect the leads to the primaries of the two power transformers.
5. Ensure that the leads remain isolated from other components and oven chassis by using insulation tape.
6. After that procedure, reconnect the power supply cord.
When the testing is completed
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge two high voltage capacitors.
4. Reconnect the all leads removed from components during testing.
5. Reinstall the outer case (cabinet).
6. Reconnect the power supply cord after the outer case is installed.
7. Run the oven and check all functions.
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