How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Justin Your Own Question
Justin, Appliance Technician
Category: Appliance
Satisfied Customers: 829
Experience:  Owner of Shaffer's Appliance Service
Type Your Appliance Question Here...
Justin is online now
A new question is answered every 9 seconds

This is a combo electrical/appliance question... Microwave

This answer was rated:

This is a combo electrical/appliance question...
Microwave and under the cabinent halogen lighting on the same circuit are malfunctioning. The lights don't come on. I checked the bulbs and a couple appear to have dark spots but the filaments are intact. Are they like Xmas lights when one goes thy all go?

The microwave underwood lights stop working so I changed a bad bulb and as well the unit did not heat although the panel command worked. Tray rotated but no heating. Then miraculously the unit started working but the lighting did not function correctly. It has a dual function "nightlight" function as well as on/off switch. Only the nightlight function was operational. But the heating was going well.

Last night th front panel stopped working but came back again this morning. I used It to heat some coffee in a paper cup and it heated but burned the cup. It also sounded funny and the rotating plate did not rotate. I came back a short time later and the lights were out on panel again.

I checked the motor under the unit with my ohm meter and it is not open. I checked the fuse and it is also not open. I put the fuse in and after putting panel back on the lights are back on. The unit heated the same cup without burning it but the tray does not rotate. The unit is also showing ohm reading through the cord which before I pulled the fuse out it did not. So...whew...the nit seems to be functioning but here are my issues/??
1. The non-rotating tray.
Could it be breaking? It is a replacement of about a year old. I see a on/off relay for the tray motor. Should I trace the wires to it to SE if it's bad?

2. Is the burning cup an indication that this unit is going bad or becoming dangerous?

3. Is there some relationship between the lights and microwave both having problems. The breaker is not tripping. I have not looked at it to SE if it's damaged in some way. I have had some breakers blow intermittently?

I'd highly suspect the control board with all the issues you're having. Turn table malfunctions can and are caused by either a control failure or a faulty door microswitch. However, since most of the issues you're having are low voltage circuits, it points to an issue with the control board. The Ewave units are NOT Whirlpool. They are Ewave. I would pull the board, check for ALL solder joints and/or burnt circuit paths. Make sure there are no cracked solder joints. Use a magnifying glass under bright light. Also, check the microswitches if you can. The no heat and no turntable could be a malfunction of one of the door switches. The one thing that is NOT controlled by a door switch is the panel lighting... this is why I believe you have a control board issue.

Customer: replied 4 years ago.
OK...I understand about looking at control board with mag glass. When you refer to micro switches could you be more specific? Are these "intermittent problems" I am describing caused by nothing else? Would checking the door switch be doable by disconnecting its leads to see if it's open? Any thoughts on lights on same wiing or should I go to electrical expert?

Are you referring to the lights on the microwave?

The door switches: There are usually three of them. You might check for a faulty connection, or you can pull the wires off (take a photo first) and do continuity checks. NO, NC, and COM are labeled in embossed plastic. Still, I think you have a main board issue because you're losing your display. Double check all the wiring for poor connections, and as I said, take the main board out and look for bad solder joints. You may find a faulty connection at the board low voltage transformer. This is what produces the voltage to close the relays. With all the problems of not heating sometimes and no turntable sometimes, I'd be suspecting a bad microswitch, but not with the display issue. Every symptom could be due to a faulty board though..

Customer: replied 4 years ago.
In the explanation of my problem(which was quite detailed I know) I described that on the same conductor as the microwave there is arun of halogen lights under the cabinets. These are the lights I mean and I wonder if like Xmas tree lights if one bulb goes does it knock the entire run out. All the filaments are intact but some of the bulbs are discolored a little dark.

After examining the circuit board I noticed a charred area in the connection between "com mgt" and R6. I don't know if this would equate to the symptoms. If I didn't mention the lights on the display are back on and it's working. If I have described "burnt circuit path" correctly then what re my choices...
Can I expect that it might go out again?

If the best suggestion is to replace the board how can I order a model number. I only see numbers on the transformer?

I'm still not sure how to check micro switches ?
Ok I understand. I thought you meant the halogen lights under the microwave. I didn't realize they were not part of the microwave. I doubt they are like a series Xmas light circuit to answer your question. I am not a lighting expert though, but most light arrays in halogen are wired in parallel. As for the burnt area, snap a photo of it close and attach the file to here using the paper clip icon. Sometimes charred areas can be repaired. I'll need to see it.
Customer: replied 4 years ago.

lets see if i can add a photocircuit board

Here is the good news: strip a one inch piece of insulation off of a 16 gauge wire. Twist the strands tightly, then tin the wire with solder. Clip this piece off. Place it beside your solder pads that the path is burnt off, and solder it in. The only bad news is that a short caused this, possibly burning out other components. But.... Repair that and you'll know soon enough. I apologize about the halogen light misunderstanding. You see, a lot of microwaves now employ halogen in their lighting, and I was confused as to the wording. Thank you for clearing that up. Repair that burnt path and let me know how things are because I do care for my customers.
Customer: replied 4 years ago.
Let me make surevI understand. What you mean by "tin the wire with solder". Does this mean to melt some solder on a length long enough to cover the distance between the two bumps where the charred circuit is and then add more solder to that which should hopefully restore continuity . Btw...16g copper wire is OK? Like from speaker wire. Laying a path of hot solder doesn't do the same thing?
Yes, tinning means to heat the conductor (wire) and melt solder on it. This stiffens it and relieves any gaps between the wire (cable). Yes, 16g copper wire is perfect. No, you can't just lay a path of solder. Although solder is conductive, it is not a proper conductor for carrying current to a load. Sorry for the delay, there were site issues today.
Customer: replied 4 years ago.
I performed the soldering to reconnect the two bumps. Now the touch screen for numbers 1-3 don't respond. I can turn the fan on but not off. The clock button does not respond. I wouldn't call them touch..they click when they are pushed. The start button will not begin a cycle so basically the microwave is really non-functional now.

Also I notice that the transformer is always very warm to touch when I remove the board. That's not normal is it? The control switches are not prt f the board. What does it mean that they now don't work correctly if the soldering restored the connection?

Do we now need a new board as well as control screen? Would a new board restore the controls. Did restoring the connection knock something out. Now no microwave t all? Unplugging the only way to get reset
If the problem got worse after bridging that open circuit path, then yes you'll need to replace the board. I did mention that this was caused by a short and other damaged could have ensued. It is always something I try prior to board replacement. 50% of the time, it takes care of it. Other times, a triac or diode, or a combination of components may have been damaged in the short. Whatever opened that circuit path drew a lot of current. Sometimes it's a bulb blowing that causes it, etc.... I doubt your panel is damaged if it was working prior. Probably just a new symptom since you repaired that break. Anything else I can help you with?
Justin and other Appliance Specialists are ready to help you
Customer: replied 4 years ago.
Yes...source for the board. I have used in the past unless you know a source? Sorry for the delay in getting back. I am also helping a neighbor whose husband is never around to fix things and I was looking at a washing machine that fills with water but won't complete the cycle. I used a screw diver to trip the door switch while filling but it won't go further. any ideas? It's analog so no diagnosis codes...

I don't see a way to give you credit but once I do we can start on the washing machine
Customer: replied 4 years ago.

I talked with customer service and thay fixed the isue bout paying you. Couild you please tell me if is a good source for boards and if model number will do to identify. I had trouble finding info on Ewaves using the model number from the unit itself.


On the washer which fills but won't cycle past filling. Its an analog so can't get a code. I open the door and used a screw driver to initiate door switch but nothing happend. Does it sound like a bad door switch or/and should I start a new question?

Hi Roderick,

Sorry for the delay.. Holiday weekend and all. The part can be purchased following this link.

Yes, you would have to start a new question. We're only allowed to answer one question per thread. Site policy. However, I think you're on the right track :)

Justin and other Appliance Specialists are ready to help you
Customer: replied 4 years ago.
Electrical expert says may have a loose neutral that I am still trying to find as to why circuit on MW and light blew so that it wont happen again.
A poor neutral would cause issues, but causing something to blow is not one of them. It's merely the return feed. However, it's definitely something to check.