This is usually caused by either a bad door switch, a loose door switch mount, or occasionally a problem on the control panel.
Even though a door switch clicks, it may still be bad inside. Its continuity must be checked.
switch or mount trouble can be caused by slamming the door or by
opening the door while it's cooking without hitting the Stop pad first.
are plastic mounts inside the microwave which hold the door switches
and onto which the door latches lock when you close the door.
The screws on these mounts may be loose. If they get too loose, the switches will not be activated properly.
it's a broken tab on the switch holder, allowing the switch to rotate
just out of position. Other times, it's a broken tab on the switch
holder, allowing the switch to rotate just out of position. This tab
can be hard to see, since it is under the bottom edge of the switch.
you or someone you know decide to look into it, we have critical
information on safety, disassembly and door switches at our site, and
our link is at our listing here on FixYa:
You can find helpful exploded view diagrams and order parts by entering your full model number here
There may also
be a "mini-manual" hidden inside the unit behind the control panel or
hidden on the left side behind the grille, which is very helpful when
troubleshooting & testing.
If you think the problem is on the control panel, we repair these nationwide by mail for $39.95 postpaid in most cases.
Please write back with your brand and model number if you need further help.
We're happy to help and we appreciate your thoughtful rating of our answer.