My timer stops after 5 seconds. - Panasonic NN-T990SA Microwave Oven

You have a defective timer circuit board, which I assume is part of the main board of the microwave. If the unit is older just replace it, if it is relatively new call a Panasonic repair service and get an estimate to repair it, I think you will be shocked by the cost to repair.

Check that a "favourite" setting has not been selected. The unit may think that is the time that you want to cook. Im not sure about your model but see if there is any clear or cancel buttons to clear any pre programmed selections. If not, unplug the machine for 15 minutes to reset the controller and try it again.

The first thing I would suggest is a hard reset. Unplug the unit for a minute or so. Then plug it back in, set the clock and try again.

If that doesn't work, leave it unplugged for about 5 minutes.

Demo Mode The Demo Mode is ideal for learning how to use the microwave oven. When set, functions can be entered without actually turning on the magnetron. The microwave oven light will come on, the fan will run, the countdown will run very quickly in the display, and the turntable will rotate. To Turn On/Off: The microwave oven and Timer must be off. Touch and hold TIMER SET/OFF for 5 seconds until 1 tone sounds. Repeat to turn off.

I have a jvm1090aw microwave oven and for some reason it just stopped working. It will still count down the timer but it won't light up and turn on. Also there is a small microwave icon flashing at the bottom right of the screen. Any ideas? Today I tested it again and started it for 30 seconds. The first 8-10 seconds nothing but silent counting down then it turned on for the last 20 seconds. It then turned on again when I tried it immediately after that but nothing 5 minutes later.

Operating functions:
To set the clock, press and hold the clock/timer button for three seconds. A clock icon will appear on the left side of the screen. Input the time using the numerical buttons and then click the clock/timer button to save the time.
To set the timer, press and release the clock/timer button so that the display shows all zeroes. Enter the desired time using the keypad. Press start/stop to start the countdown. The countdown may be paused by pressing the stop/start button and resumed by pressing the same button again.
When countdown is complete, timer will beep continuously for thirty seconds and display will flash. Timer will then beep every ten seconds for ten minutes until the stop/start button is pressed.
This timer will also time up to time activities. To start count up, press clear/memory so timer reads all zeroes. Press stop/start and a plus sign will appear on the right side of the screen as the timer begins counting up.

Sounds like your timer board is fried. Replace it.

you have a bad inverter board.

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

Is it 5 seconds or 5 minutes? The difference coulsd be important, but either could indicate a bad magnetron.

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

Please write back with more details if you need further help.

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