It not cooling

The unit could be overheating and shutting down, cooling off, and restarting. Check ventilation holes on back for dust accumulation and blockage. Check that cooling fan is turning properly.

This one actually sounds like the unit is cooking when the door is closed without blowing the fuse as it is supposed to do. Unplug it from the wall and let it cool down, which it probably already is. Put a cup of cold water in it, close the door and plug it in for one minute. Unplug it from the wall and check the water. Did it heat up? I'd bet that it heated the water up. Sometimes the cook relay sticks closed and it stays in cook mode. This condition is supposed to blow the fuse but really rarely it doesn't. I've only seen this happen 3 or 4 times out of about 14,000 units I have looked at in my career.
It would need a new control PCB and new door switches and probably a new magnetron.

HELLO.

Solution to your microwave problem is given as below.

* 1 Set your Daewoo microwave on a countertop near an electrical outlet and plug it in. Open the door and place the circular roller guide in the center of the oven cavity, then place the glass cooking tray over it.

* 2 Set your food on a microwave-safe dish and then put the dish on the cooking tray and close the door. Make sure that it latches properly.

* 3 Turn the upper knob to select a power level. Power levels include "Defrost," "Med-High," or "High." If your Daewoo has a touch pad, touch the "Microwave" button once to set the highest power level. Touch it consecutive times to lower the power level.

* 4 Turn the lower knob to set the cooking time. For cooking times less than two minutes, turn the knob up past the two-minute mark, then back to the correct time. For touch pad models, enter in the cooking time with the numerical keys and then press "Start."

* 5 Open the door at any time to stop the cooking and check the temperature of your food. Shut the door to automatically continue cooking, or turn the timer knob to the right to add more time. For touch pads, press the "Stop/Clear" button, then key in a new cooking time and press "Start."

* 6 Open the door when the timer reaches the "Off" position and take out your food.

Thanks.

there is a thermal (white ceramic) fuse located right under the cover on the top of your microwave replace it.
an electronics part store should stock it.

It is the fan. Im guessing it only happens on combination cook and not when you are only using the microwave setting. It happens because the oven is hot and it helps to cool it quicker. It is normal. The microwaves are not working and neither is the oven-just the fan.

That's how it would sound if you were cooking on a power level less than full power.

If you enter the cooking time and hit Start, it should cook at full power by default and not cycle like you describe.

If you are using some sensor cook setting or automatic type cooking setting, it may cycle like that normally.

The first thing to try is a "hard reset". Unplug it from the power line for a minute, plug it back in, set the clock, then try again.

Let us know if the hard reset doesn't fix it.

If you don't have your manual, you can download it free here. Check the lower right area to enter your model. number.

We're happy to help and we appreciate your thoughtful rating of our answer.

Fan turned on after cooking because a thermostat got to hot and tripped turning on the fan to try to cool the unit.  The unit went completely dead when thermal fuse tripped which is located above the cavity on the left side.

We have *critical* safety, disassembly, and troubleshooting info at our site, which is linked at our listing here on FixYa: http://tinyurl.com/yzjozk If the fuse blows a few seconds after you hit START, then it's likely that you have an overheating / shorting high-voltage transformer. Try this: Let the oven set unplugged for about an hour to cool completely. Then cook for a minute at the lowest power level. If it runs any longer than it has been, it's probably the high voltage transformer, which is no longer available, but will run about $95 if you can find new old stock. If the fuse blows as soon as you hit START, then it's likely that you have a shorted high-voltage capacitor (#RC-QZA211WRE0) which runs about $25. You can order parts for Sharp models from Tritronics at http://www.wehaveparts.com.