Will not cook or will not warm

Question edited for clarity and add MAKER!

Replacements

https://www.google.com/search?q=whirlpool+30+over+the+range+microwave

They all come in standard widths. Any 30" microwave should be fine.

Whirlpool MH2175XST
1.7 Cu. Ft. Over-the-Range Microwave with 1,000 Cooking Watts, Warm Hold Cycle and Sensor Cooking Cycles: Bisque 4.6 quick specs
Style: Over the Range
Width: 29 7/8 Inch
Depth: 15 3/4 Inch
Height: 17 1/8 Inch
Capacity: 1.7 Cu. Ft.

faulty microwave module replace it

Replace thermal sw's

first suspect is the inverter board (power) and magnatron a distant second----in either case the part involved unless an expensive unit is pricey.

Hi, if it is an inverter microwave and the problem is cycling every 2-3 seconds, my experience is the magnetron has most likely gone short circuit and the inverter board is shutting down to protect itself and then restarting, hence your symptom.
DO NOT try to test this unless you are experienced with extra high voltages - the voltages present/stored in a microwave even when powered off can kill you.

See if this describes what's happening:

• Put in time, push start and unit runs for 2 seconds, relay clicks, unit goes off. Cook time on display goes off and clock time comes back. Bad upper interlock switch and charred connector

If so, see http://207.234.249.73/mwd/safety.txt , http://207.234.249.73/mwd/disassembly.txt and http://207.234.249.73/mwd/doorsw.txt

Otherwise, if the digital programmer circuit / controller does not get a feedback signal from the inverter for a period of 3 seconds, the controller will stop the cook cycle.

That may be a loose connection in the wiring between the inverter, magnetron, and/or control board, or maybe one of those components has failed.

Due to the lethal voltages used and produced in inverters, I do not recommend that an inexperienced person work on these.

You can find an authorized Panasonic servicer here.

In Canada, you can find an authorized Panasonic servicer here.

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

You didn't mention your brand or model number, but I'll assume it's a Panasonic since you posted this under a Panasonic category.

See if this describes what's happening:

• Put in time, push start and unit runs for 2 seconds, relay clicks, unit goes off. Cook time on display goes off and clock time comes back. Bad upper interlock switch and charred connector

If so, see http://207.234.249.73/mwd/safety.txt , http://207.234.249.73/mwd/disassembly.txt and http://207.234.249.73/mwd/doorsw.txt

Otherwise, if the digital programmer circuit / controller does not get a feedback signal from the inverter for a period of 3 seconds, the controller will stop the cook cycle.

If it stops after 7 seconds, it has a problem with the inverter.

If it stops at 16 seconds and is a sensor model, it probably has a defective humidity sensor.

If it stops after 22 seconds, that means the controller has detected a problem, usually a problem with the inverter, controller, magnetron, or a bad connection from one or the other.

Display codes H95, H97, H98 or H99 mean that there's a problem with your inverter, magnetron, or digital programming circuit.

That may be a loose connection in the wiring between the inverter, magnetron, and/or control board, or maybe one of those components has failed.

Due to the lethal voltages used and produced in inverters, I do not recommend that an inexperienced person work on these.

You can find an authorized Panasonic servicer here.

In Canada, you can find an authorized Panasonic servicer here.

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

See if this describes what's happening:

• Put in time, push start and unit runs for 2 seconds, relay clicks, unit goes off. Cook time on display goes off and clock time comes back. Bad upper interlock switch and charred connector

If so, see http://www.microwavedisplay.com/safety.txt , http://www.microwavedisplay.com/disassembly.txt and http://www.microwavedisplay.com/doorsw.txt

Otherwise, if the digital programmer circuit / controller does not get a feedback signal from the inverter for a period of 3 seconds, the controller will stop the cook cycle.

That may be a loose connection in the wiring between the inverter, magnetron, and/or control board, or maybe one of those components has failed.

Due to the lethal voltages used and produced in inverters, I do not recommend that an inexperienced person work on these.

You can find an authorized Panasonic servicer here.

In Canada, you can find an authorized Panasonic servicer here.

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

If the digital programmer circuit / controller does not get a feedback signal from the inverter for a period of 3 seconds, the controller will stop the cook cycle.

Due to the lethal voltages used and produced in inverters, I do not recommend that an inexperienced person work on these.

You can find an authorized Panasonic servicer here.

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