Hi, I have a Kenmore 87103 microwave and it has started acting up lately. When I place something in the microwave and set the timer, the timer counts down however the microwave doesn't work (no sound and food/beverage doesn't get hot). The following has worked for me and don't know if they are related: 1. I open the door and shut it again and restart the timer - works sometimes 2. Do a power reset - unplug the microwave and replug back after 1 min - works sometimes When it works, it works well. Why do I have this intermittent issue?

SOURCE: Microwave does not heat

Just had the same experience with the identical model. Removed the cover (a challenge because of the security screws), revealing valuable troubleshooting directions intended for an experienced technician. However, I think the info is well within the reach of a typical DIY person, does not require any dangerous power-on conditions. However, make sure that you discharge the HV capacitor before trouble shooting. In my case, it appears that the HV diode is open, have ordered a replacement on the internet for $3.18, easy to replace. Hope it works. Good luck.

SOURCE: Emerson Model MWG9111SL Microwave not always working

Every thing works, but no heating and no noise. I am happy you had noticed that there was a difference in the "Noise". Some describe it as a vibration you can feel in the cabinet. The "Noise" is only present when the High Voltage Transformer is engaged. The "Noise" is a low Humm which The High Voltage Transformer emits. Without The High Voltage the unit will not Heat.
BECAUSE you say it heats Sometimes. I suspect a LOOSE CONNECTION between the Low Voltage (115v) and the Primary of The High Voltage Transformer. Could be a Solder Connection, or just a Loose Wire. Loose, not Open. If it were OPEN it would not "Cook" at anytime.

William Miller

• 9179 Answers
• Posted on Sep 16, 2008

SOURCE: MMV5000BDW Touch panel works intermittently

You have a failing keypad.

If you (or someone you know) might want to replace it yourself, I have uploaded a handy guide with pictures showing you what's typically involved.

You can usually find helpful exploded view diagrams and order parts by entering your full model number 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.

If you would like to have us do this for you, we do that for $39.95 plus part costs.

Please feel free to contact me directly if you need more help.

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

William E. Miller, AS-EET
[email protected]
http://www.microwavedisplay.com

SOURCE: Food won't heat up

Hello, I had the same problem, and just fixed mine. Start by turning on your microwave (on mine, the light turned on and timer worked, but the fan nor the plate turned)... push the door upward and see if the microwave turns on... (mine did). so far so good. open the door and take the upper hinge cap off with flat head screwdrive. take the door off and place a small washer on the bottom hinge, put the door back on. your microwave should be good now. essentially, the door just needs to be pushed up a bit so it will work.
good luck, hope that works for you...

SOURCE: Microwave Oven EM-804T

When I opened up the microwave cover, noticed that the door latch mechanism was worn and not holding up the interlock switch. A thick piece of tape on the worn piece of plastic and microwave was back to working (I had symptom of the timer counting down without the microwave turning on)