AMC5143BCB - Instructions

Removed case,
Discharged HV capacitor and removed cooling fan.
Unscrewed ground end of HV diode and unplugged from HV capacitor.
Installed new diode by reversing the order. In my case, the problem was the magnetron was bad, so I replaced it as well.

Snipped four corners off inspection panel,removed one phillips screw and two elect. Connections. Reverse process.

Got the part and replaced it. Simple. Pleasure to work with

Other tools that are usefull long needle nose pliers, long thin blade screw driver and small magnetic flashlight. Place the microwave on a work bench and remove the case it cover 3 sides. Place the microwave on a chair so it can stand with the controls up. You are replacing the lower door microswitch. The switch is located behind the control panel in the lower part of the area. The switch is several inches inside this area and your hands will not fit. Take care when moving wires and a couple of sensors. Use the thin blade screwdriver to release a tab holding the switch in place. Do not break this tab. Take the needle nose pliers and remove the switch. Put the wires on the new switch, open the door a short distance so a door lever moves enough to put the microswitch back into the bracket.

Ordered (most difficult part of repair, because I wasn't sure the one I ordered would fit), opened box, removed padding, opened microwave oven door, lined up center indentations with center and my repair was complete. Placed a cup of lukewarm coffee on the tray, closed door and pushed auto 30 seconds. The cup went round and round on the plate that went round and round and then, the END chime sounded. Success! Lukewarm coffee has been transformed to HOT coffee on the newly installed cooking tray.

removed a dozen screws-discarded large cap-replaced diode-replaced a dozen screws(took longer to replace them than remove for some unknown reason). Microwave now works(wife happy).

1. Order correct light bulb for unit and have it with you before removing old lightbulb.
My Microwave is built into cabinet.
2. Disconnect power (Either turn breaker off or unplug unit from wall)
3. Remove face cover on cabinet. (4 Phillips head screws)
I was able to reach in the opening in the cabinet and unplug from the wall.
4. Remove Phillip head screws holding microwave in cabinet.
5. Remove microwave from cabinet.
6. Remove Phillip head screws and torx screws holding outside cover on the back of unit and the side (1 on right side) and then remove cover.
Light bulb is on the top front right side.
7. Remove 1 philip head screw holding light bulb and unplug quick connector wires.
8. Plug quick connector into new light bulb same way it came out and place new light bulb in place and put the 1 philips head screw holding it back in place.
9. Put cover back on and all the screws. Temporary plug the unit in to test light bulb works before securing it back into cabinet.
10. Reverse order 5,4,Plug unit in wall before putting the face back on.
Done.

Access is via RT. SIDE Panel as you face microwave. There are three screws on the bottom right edge to loosen. After that the side panel slips down and off. the fuse is located in the rear near where the power cord comes in. It is the white ceramic tube 1/4" in dia. and 1-1/2" long. Pull it out like any fuse and replace with new one. Reassemble and you are done!

I had to unmount the over-the-range microwave oven to be able to gain access to the interior of the oven. Complicating removal (and re-installation) was the fact that there is a "pot-filler" faucet installed directly underneath the oven. In retrospect, I should've removed the faucet before doing the repair, but "c'est la vie."

After I got the microwave down, removing the case was also "interesting." I get bonus points for the fact that the previous owner must've had to replace the same diode before - and then re-assembled the microwave case incorrectly - thereby adding to the confusion (BTW, the service manual that I found online said nothing about how to remove the oven's case).

To remove the case, undo all the screws holding it on, and then rotate the case upwards from the back while also pulling the case backwards. There are crimped folds on the inside of the case that mate with the back edges of the front of the oven's chassis, and these folds have to be unclipped from the chassis in order to remove the case.

Replacing the diode itself was the easiest part of the job. The two connectors on the diode are of different types, making it impossible to install the diode with the wrong polarity.

BTW, the diode that had failed was not an OEM diode; I suspect it was a generic component that had been installed by a repairman sometime between 2004-2008 (when our home's original owners still owned the home). On the other hand, the new diode from PartSelect is an OEM part (it came packaged in a sealed Whirlpool bag).

The fact that the oven had stopped heating indicated that it was either the high-voltage diode or the magnetron that had failed. Since a replacement diode costs ~ 1/10th as much as a replacement magnetron, I figured it made sense to replace the cheaper part first. Fortunately, this fixed the problem.

One last thing: I tried testing both the old and new diodes for conductivity and polarity using my volt-ohm meter (VOM), but I was unable to get either diode to "turn on," even though my VOM is powered by a 9-v battery, and I used the 2-Mohm range setting. I guess the test voltage of my el-cheapo VOM isn't high enough to exceed the diode's threshold voltage, (even though I have successfully used this same VOM to test low-voltage diodes).

There were two hard parts for me to work through.

The first was breaking off the two screws that need a special head screwdriver to remove. None of my special special head screwdrivers worked (I have a few), so I used a hammer to force them off.

The second hardest part for me was finding the correct replacement bulb on-line. My Amana Microwave is a combo Microwave/Convection type, and it's a strange little bulb - almost tube like.

Once I did find the right bulb on this PartSelect.com website it was a breeze. The part was delivered in just a couple of days (even during this Covid-19 pandemic). Once I had the replacement bulb in hand it barely took 5 minutes to install.

Thanks PartSelect!!

Required that i remove the built in frame and mounting. Required tamper proof socket to remove housing. I removed the old bulb and simply replaced and reverse installed the cabinet.

pull out broken button
remove spring from broken button and place on back of new button
press new button with spring on back into
microwave

Removed cover, found bad thermal fuse ("Thermostat"), disconnected the two wires, replaced bad "Thermostat", reassembled;
Saved alot of money not replacing an almost brand new microwave.

I ordered a replacement piece. Fits perfectly and rotates as it should. It arrived earlier than planned.

You have to remove the cover which in my case was a little more difficult because the unit is wall mounted and has a frame around it. That was the hard part. Once the mounting frame was removed, you can remove the cover and the light bulb is on the top right side of the unit. One screw removes it and the new one pops right in. Put the case back on reinstall it in the wall and voila...piece of cake.