Check whether there is a proper power supply. Look to see whether the cord is connected to a grounded 3-prong outlet and the cord is fully plugged in. If the electrical system is built-in and no power cord is visible, replace or reset the household fuse or circuit breaker.
Some basic microwave operational steps may affect whether the microwave is heating. Open and close the microwave door, as the unit will not function with the door open, and push “Stop/Clear” to cancel any previous settings, such as the timer, which do not heat the microwave oven.
Once the power to the microwave has been reset, or verified as working, and the microwave is ready to run, select a new cook cycle and press “Start” to see if the microwave begins to run and cook food as expected. Allow the food to cook for the alloted time and then open the microwave door and check to see if the food has cooked or heated. Choose a longer cooking time and restart the microwave if food is heating but is cooking slowly.
If all efforts to troubleshoot the function and power to the microwave still do not get the appliance heating food as expected, there may be a repair issue that needs to be addressed. Contact Kenmore or another professional technician for advice.