Shutting Off Prematurely

There are sixty seconds in a minute, so 1 min 60 sec is the same as 2 min. If you want 40 seconds less than 2 minutes then set it for 1 min 20 sec or for 80 sec.

It does sound like the magnetron is failing, when it shuts down it is because the thermal fuse is detecting to much heat from the magnetron and shutting it down, I might add this part is the heart of the system, rough cost would be in the area of $100.00 maybe cheaper. Intallation of this part is very tricky and there is the danger of high voltage, I recommend a pro for safety and correct installation.

This sounds like a magnetron problem, if it gets to hot, there is a special thermal fuse that will open up if it senses abnormal temperature rise from the magnetron and after a cool down period it will reset itself. In rare cases I have known the thermal fuse to become defective and cut out prematurely. My feeling is replace the oven! because by the time you get a appliance repairman in for a sevice call and parts you probably could have bought a new microwave oven.

I had a similar problem--no manual--but found this way to set the clock:
1) Be sure colon is flashing (unplug and replug)
2) Press the 10 HOUR/MIN, 1 MIN, 10 SEC/MIN, and 1 SEC/MIN buttons until the correct time displays.
3) Press the CLOCK button.
Hope this helps.

All electronics work but microwave won't heat.

Hi! the problem you have stated indicates that the magnetron its not functioning, check for busted fuse.

Sounds like the power inverter

In most cases, this is a problem with the inverter or a bad magnetron.

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

I would recommend that you contact your nearest Panasonic-authorized servicer. You can find one here:
http://www2.panasonic.com/webapp/wcs/stores/servlet/vServiceLocator?storeId=15001

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

In most cases, this is a problem with the inverter or a bad magnetron.

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

I would recommend that you contact your nearest Panasonic-authorized servicer. You can find one here:
http://www2.panasonic.com/webapp/wcs/stores/servlet/vServiceLocator?storeId=15001

Could be that magnetron is not receiving adequate cooling thus causing thermal protector to open. This is mounted on the magnetron.