Adds extra minute

https://www.fix.com/repair/appliance/microwave/doesnt-shut-off

Does it have a turn table that spins your food container? If so, does it turn? If not, you are getting a solid directed beam of microwaves focused on one part of your food leaving the rest of it ignored. If it doesn't have a turn table, it will have a wave spreader inside which is nothing more than an aluminum fan that is sometimes driven by a small motor and rubber belt. You won't see this as it is inside the chamber that contains the magnetron that generates the microwaves. These belts can break allowing a solid, focused microwave beam to shine on your food rather than be distributed around the oven, again, leaving the rest unwarmed. If this is the case, using the oven can damage it over time. If you don't know what you are doing, DO NOT try to repair it yourself!!! If you don't get the outer casing back together properly, you can expose yourself and / or your family to dangerous amounts of microwave radiation. You should take it to a qualified service center for repair but I would venture a guess that it is already damaged because of your statement "but getting increasingly unreliable". Even if it isn't damaged, it will probably cost you more in labor to fix it than it would cost to replace it. Good luck.

If the delay in heating is exactly the same each time, you might have some sort of control panel problem. If it is approximately the same each time, you may have an intermittent magnetron that is failing to oscillate until the heater reaches a high enough temperature to emit an adequate number of electrons.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/david_29ad5d1dd86564b0

Only place I've found is here: CorningWare Browner Instructions

As these dishes were designed by Corning for a 650 watt over, you can recalculate preheat and cooking times for your oven with the following formula:

650/(your oven's wattage) x (listed preheat time or cook time)

For example, for a Corning MW-9 dish, they list 4 minutes maximum preheat time. I have a 1,580 watt oven. So 650/1580 = .41 x 4 minutes = 1.64 minutes and about a minute and a half preheat. (MAX).

Start out with just a few seconds if you are heating something and increase it if it isn't heated through, Sounds like the wattage is high on your unit or you are using too much time. Don't over do it. Just use a few seconds or a few minutes. Don't use the pre-sets if they are burning your food. Just punch in the seconds or minutes yourself until you learn how much time you need for the food you are cooking or heating.

Un plug it or disconect it and then switch on again

Many timers are sold under different brand names with different numbers.
For example Westek TE06WHB is same as Woods 59377

Sometimes different timers are packaged under same number, for example Utilitec TE06WHBL is shipped as the old Woods TD1300.

GE and Utilitec sell the same timer with different numbers.
Westinghouse and Stanley and Utilitec and Woods overlap.

I got manuals for some, and can sometimes cross reference if you describe the timer.

1) take a minute and add a comment with description of button layout with button names, or describe the dial and switches. Be as detailed as possible.

2) Look through timers on following links and see if your timer shows:
http://waterheatertimer.org/Woods-timers-and-manuals.html
http://waterheatertimer.org/GE-timers-and-manuals.html
http://waterheatertimer.org/GE-timers-and-manuals.html

Add a comment for more free help.
Also take advantage of fixya phone service.
For a price, expert speaks with you over phone while you work on timer or any do-it-yourself project.
Fixya is always less expensive than a service call.

HI. your control board has failed. you will need to replace the control board asap if possible.

your microwave magnetron part is probably broken you need to send this to a shop im afraid, might cost you 40- 60 $
cheers

Hi , open the cover with philips screw driver , b sure unplug it first , If you have continuety tester check the fuse if open replace it , are available in electronics center brings that sample and insert it.