most likely answer is the turntable motor is defunct. only accesible usually by opening up the cut out port on the base. Also it is possible the centre drive under the plate is burnt or distorted.
patrick
June 2012
on most ovens the outside cover need to be taken off and there is a small motor under the oven area that need replacement,best to do is turn oven on back and see if maybe their is big inspection panel at bottom.ensure correct motor is fitted as they come in different voltages
jj
June 2012
Automatic Answer
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