Why did the latch switch J61424tooap connector melted, could it be because of 3spots of bare metal on door frame?

Sounds like door switch problems, you say you replaced the door latch but did you replace the door switches too. most newer units have door switches with small 3/16 terminals and small undersized wires going to them so they get how and melt the plastic body of the switch and it causes a back feed of voltage when it is not supposed to be there. Check under the blades of the switch and see if you have any melted plastic of the switch body there, that will be your bad switch I recommend replacing with a switch with 1/4 terminal, they hold up to the current much better. Change the wires to the switch with larger ones that can handle the current better without getting hot

The inside of a microwave oven has a special paint on it. If the paint becomes damaged, the microwaves strike the bare metal and arc. This leaves a burn mark. It will also ruin the magnetron inside the oven.

If your want to start the easy path, get a Q-tip and some light weight grease and lightly grease the door-switch levers inside the door latch holes and see if that solves your problem. If not, then you will have to remove the cover, and likely you will find the door switch assembly and it's metal mounting support are bent on something of an angle - the switch assembly should be at 90 degrees to the front of the microwave oven so that he door latch fingers can slip in and activate the control switches easily all at the same time - straighten the switch frame which may require you to remove the switch bank temporarily. The little bit of grease still doesn't hurt to do it.
Reassemble.

Since you posted this under the WMH32517AT category, I'll assume that's your model number. If not, feel free to e-mail me (below).

The function of the door switches is to prevent the oven from running when the door is open.

If the switches fail in a certain way, it can cause the fuse or breaker to blow. That's by design.

Some models have a line fuse and another fuse for the controller low voltage transformer.

There is a technical sheet hidden behind the grille or behind the controls. It's very helpful in locating components and testing, etc.

Your door switch mounts need to be inspected to be sure they're not loose, misaligned, or damaged. If so, they'll need to be realigned or replaced as needed.

The hook-like "latch heads" protruding from the door must be under spring tension and must move up and down freely in order to activate the door switches.

It sounds like your door switch is stuck, and you can order a universal type here.

Most door switch problems are caused by slamming the door or opening the door while it's cooking instead of hitting the "Stop" pad first.

At my Web site, I have a video available showing how to remove a typical over the range grille and control panel assembly in under 5 minutes.

The support page for model WMH32517AT is here. It has the owner's manual, installation instructions, exploded views, and parts lists.

You can order any needed Whirlpool parts from the Pros here, my favorite affiliated supplier.
For more free DIY and other help & advice, feel free to contact me via my site.

Please include FULL model number*, FCC ID number*, + detailed symptom information. ( * on the tag in cooking cavity or around door frame or control frame or on back)

William E. Miller, AS-EET
http://www.microwavecontrol.com
Microwave Oven Control Panel Repair Nationwide
"Recycling by repairing since 1982"

I have an Emerson MW8999RD that all of a sudden yesterday wouldn't latch. I don't think you have to, but I took the door off (three screws hold the case on which needs to be removed to get at the top hinge). Then I took off the inner plastic picture frame - pretty easy with a thin blade to move the fragile tabs. Then I removed the metal frame that has the little microwave blocking holes. This was the hardest part because the plastic retaining tabs are even more fragile and I broke one. Then I found the loose spring due to broken plastic hook as described above. I was able to make a new hook by simply looping a small zip tie where the old plastic hook tip broke off. Now works great!

Plastic will melt but the door frame is metal and will not. So there is no safety issue here, just looks.
One could replace the door assembly if required. I would leave the door open after convection cooking to let the heat escape without heat build up causing the plastic to mishape.

This heat could have come from excess current draw due to a failing part, such as the magnetron, or an improper voltage level at the outlet. It should measure 105-125VAC.

A loose connection can also result in heat and melting.

I would recommend replacing the section of wire that's melted. You need to make a good solid connection with proper wire nuts and solid crimped connectors.

If you think the TCO may have been stressed, it should be replaced, too.

I would also check the fuse holder by seeing if you can twirl the fuse with your bare fingers while it's in the holder. If so, then it is too loose and the holder must be replaced.

You cannot just squeeze it tighter with pliers, because metal fatigue will make it go loose again, possibly resulting in a melted fuse.

Lastly, I would replace the primary interlock (top door switch). See http://www.microwavedisplay.com/doorsw.txt.

Then make sure that no one opens the door while the oven is cooking unless it is specifically called for in the cooking cycle. Opening the door while it is cooking leads to premature switch failure and heat / melting of the switches connectors and wiring.

You can find the full service manual online here.

Yours may have the revised circuit. You can see the "mini-manual" for that version here.

There should also be a "mini-manual" hidden inside the unit behind the control panel or hidden on the left side behind the grille, which is very helpful when troubleshooting, & testing.



At our Web site, we have a video available showing how to remove a typical over the range control panel assembly in under 5 minutes.

You can find links to helpful exploded view diagrams and part ordering help here.

I'd recommend that your bookmark this link to your favorites.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

If you gently push up on the door latches (hook-like devices on the door) there should be spring tension. If they just flop right up, the spring is off.

Normally the problem is not the spring, but a broken spring mounting tab on the door latch head (hook) assembly or the inner door panel.

If it's the door panel, it's usually easier and cheaper to use epoxy and some kind of hardware to fashion a new spring mount.

The door latch head (hook) is easy to replace or repair if that's the issue.

We have critical safety & disassembly info at our site, linked here.

Normally you have to separate the door panels (as shown in the attached photo) and then you'll see the screws you need to remove.

Or you can watch a YouTube video (not a video I made) here that demonstrates how it's done.

The best place to order Panasonic parts is Tritronics. You can also call them at 866-779-5835.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

There're some half a dozen or so small screws securing that frame to the door face. These screws must be removed. Then, the frame can be pried out by releasing the plastic snappers (with a flat screwdriver) while in the same time gently helping the frame to detach from these snappers' hold and the door face. It's a tidious, somewhat annoying task. The snappers may and will even likely break in the process, but aren't needed for the frame to be resecured to the door face after the handle is replaced. Note that the broken ends of the handle must be held with a pair of pliers or a flat screwdriver needs to be inserted bewteen each of them and the hole, or the ends will turn with the screws. This is because the metal screws' grip of the plastic handle broken ends is very strong and otherwise won't get separated.Once the above is accomplished, reassembling the door is a brease.

P.S.: The dual end latch may interfere somewhat with the job and can be removed for the process to be undertaken without it disturbing. It's easy to remove and replace that latch, including its spring.

theres a small plastic hook inside the door which holds a tension spring this will have snapped off stopping the latch from entering the lock its actually quite easy to fix the inner plastic frame can be unclipped with a small flat blade screwdriver exposing the hook mechanism and the spring will be lying in the bottom of the door frame you can reconnect it to the metal inner frame it stretches the spring a little more but it will never snap again ive done this loads of times with no probs otherwise you will have to replace the outer door to reinstate the broken hook.