Microwave doesn?t turn on

Be-safe, Un-plug your microwave oven ,

Open the microwave cover ,
Close and open door few times to check the door latch(es) and switch(es).
Door switch assembly may has one or more micro switches.( Most switches are black or grey and about 1,25 in long X 3/4 in wide X 5/6 in thick with two or three wire connections).
Making sure door latch close and open these micro-switches.

You can hear the switch "clicks" when small switch pin or lever is pressed.

Sometime these door micro-switches pin or lever get stuck or broken.

You can take couple pictures before remove wires or micro switches

You can buy these switches for about 3-7 dollars online. Some web sites have video showing how to check them. (Using Volt-Ohm meter)

If there is no power at all to the display or the panel then it is failure of the board. But if there is power without heating, if the turntable/fan/light works, then it can be related to failure of relay, Magnetron, Waveguide or capacitor.

I would strongly consider replacing the microwave oven, prices have dropped considerably. The problem you are describing is in the keypad controller board.

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 and try again.

If it still won't work, then you may have a bad membrane keypad / DP circuit.

If your model is NN-P295SF, the service is here.

Parts can be ordered from Encompass here.

You can modify a standard, typical micro switch available at many places or, you can get an exact replacement from GE parts placed or you can try www.repairclinic.com or you can try a FixYa.com advertiser.

You are correct in trying the safety interlock switches ... they cannot stand the opening and closing of the door while the machine is running. To improve the live cycle of these tiny switches is NEVER open the door while the oven is operating.

Thanks for your question @ FixYa.com

Unplug micro, clean inside with warm water, the seal around door also. Then DRY THOROGHLY, plug in and try your coffee.

I had this problem too:
it turns out that it (apparently) just needed some 'warm-up' time!

After being plugged in for about 15 to 30 minutes,
the buttons suddenly "came to life"...

Note that when it's flashing 88:88 you are supposed to _start_ with the 'Stop/Clear' button. After that, set the clock (press "Clock", enter the time with the number pad, then press Clock again).

Hope that helps.

Check those three microswitches in the latch assembly.

Pressing "timer/clock" button 4 times turns on and off demo mode.

There is a internal locking mechanisim that has 2 or more switches that is usually attached with two or more screws next to the door latch side. Crack open the micro and adjust this by shutting the door then pushing this assy toward the latches untill all the switches look like they are being pushed in fully. If this doesn't solve the problem one of the switches or possibly more are defective. Call a local appliance repair center and get a switch there called micro switches.