This one does not have a turntable shutoff option, which is available most commonly on over the range models.
You likely have a bad turntable motor or turntable support (the 3-legged part with rollers).
If yours is a Dacor DMT2420, it is essentially a rebranded Sharp model R440DK/DW / R540DK/DW.
There was an issue with the original turntable motor on these Sharps.
The new Sharp turntable motor kit is part # RMOTDA264/KIT and they are available from Tritronics at http://www.wehaveparts.com
I cannot guarantee that this is the correct Sharp part for this Dacor, but I believe it is, based on the other parts being the same.
Another thing to be sure of is that your turntable support does not have a cracked coupler (the part that connects to the motor) and you need to be sure the legs are straight.
Sometimes heat and weight cause the legs to bend so that the coupler will no longer go down far enough to make contact with the motor shaft.
To fix these, I use a gas stove burner or torch to heat up the area where the legs connect to the hub, then I turn it upside down with a weight on the hub / coupler and leave it until it cools.
This straightens the legs back, and you can do this once or twice before you have to replace the support. But if the support is cracked or charred, it needs to be replaced.
The Sharp turntable support part number is FROLPB025MRK0 and it's also available from Tritronics.
If you don't want to take the chance, the Dacor part numbers are:
66245 motor Ref # 1-11
66184 support Ref # 6-3
But it will depend on your supplier as to whether these are original parts prone to failure or the new and improved parts.
You can order the Dacor parts from sources listed here:
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