My Frigidaire fmv156dsb microwave counts down and lights work onl

That would be a bad primary interlock (bottom door switch) or its mount may be, loose, cracked, or misaligned.

We have the service / repair manual for this model and have uploaded it to our site here for free download to help you.


It will give you safety info, step by step help in disassembly, troubleshooting tips, and part numbers.

If a switch is all you need, we offer a universal type for only $5 postpaid which you can order here.

Even though a door switch clicks, it may still be bad inside.

Door switch or mount trouble is usually caused by slamming the door or by opening the door while it's cooking without hitting the Stop pad first.

There 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.

Sometimes 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.

If the switch mount is broken, it's usually more economical and safer to add a dab or two of hot glue to the mount to secure the switch. Let it cool for about 30 minutes before using.

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