Hello, Can we have the complete model number please? When you say it is a built in microwave, does it mean it is an oven top? or it is a counter top but was inserted in the wall cabinets? I asked because it would be easy to repair a counter top unit rather than an oven top one.
Hello Brian, Sorry for the delay. I would say it is a free standing but was just installed in a cup board. All you have to do is remove the whole unit off the cup board and open the cabinet. Then underneath the unit is the access for the turn table motor. You would have to cut the tin cover from its perforated spot to remove it and then you can access the motor.
I suggest you get a meter to measure the resistance first so you would really know if it is busted or not. Then replace it if found to be bad.