[jclawman]

The microwave is part of an oven/microwave combo, the microwave stopped working immediately on start up and I heard an audible pop that sounded like fuse blowing. I opened up the unit, found the fuse, ordered a new one (for $17!!) put the new one in and the unit powered up and allowed me to set a cook time but as soon as I pushed start it immediately blew the new fuse as well. Obviously, there is some other issue here any help is much appreciated!

In case it matters I will say that the new fuse came as a kit and included a "monitor" switch. The only problem is that the unit has three switches of this type in the door lock mechanism. I tested all three switches and they all seemed to be working correctly, so I replaced one arbitarily.

Finally, I bought the switch and fuse from this website and am a little upset with myself for blowing it in seconds.... can this fuse, a Bussman SC-20 Time Delay be purchased by itself?

Thanks!

[RegUS_PatOff]

standard Bussmann SC-20 Class G Time Delay Fuse, available at most harware stores.
Amazon.com: Bussmann SC-20 Class G Time Delay Fuse: Home Improvement

monitor switch #2 in this diagram
http://www3.sears.com/Paul/Leadimage.asp?productTypeID=0124100&brandID=1198&m odelDesc=27%22%20BUILT-IN%20ELECTRIC%20SELF-CLEAN%20OVEN%20WITH%20MICROWAVE&modelNumber=RM765P XBB2&documentID=O2022170&documentTypeID=PLDM&docum entClassCode=PM&titleType=DOOR%20AND%20LATCH&title ID=00010

[ripleys]

A bad door switch usually blows the fuse when the door is either opened or closed. Sounds to me like you have a problem with the high voltage section of your microwave e.g magnetron, capacitor, diode, HV transformer. I would suggest if you want to keep this microwave, get it diagnosed by a qualified service technician so you only replace the part that is required. Too many people try and fix these things just by replacing part after part after part and you end up spending a lot of unneccesary money to try and solve the problem.

[RegUS_PatOff]

the monitor switch interacts with the two interlock switches and will blow the fuse if either one of the interlock switches don't work (at the correct time).

monitor switch (red actuator) location on previous link

interlock switches (black actuator) Part Details - WHIRLPOOL Door interlock switch kit (2-pack), part number: AP3109474

#2 & #2 in this diagram:

http://www.appliancepartspros.com/se...neplpl15jj.gif

schematic:

[jclawman]

Thanks to you both for the info!! Particularly the schematic, any chance you have the whole thing or could direct me to where I could find it? I did end up taking the unit to a repair place to be diagnosed and the guy was looking for the wiring diagram but we could not find one any where in the unit. Thanks again.

[RegUS_PatOff]

I don't have the manual, the schematic was just 1 of 2 sheets of a similar model.

there is more info on the Sears website http://www3.sears.com/Paul/model_sea...num=RM765pxbb2

give him these websites and print out the above messages.