I have the same model microwave and investigated the same issue this morning. There are two possible problems: The turntable motor could have burned out, but the more likely problem is that the drive sleeve (the plastic piece with the three tabs that actually turns the glass plate) is worn out. You can determine which problem you have by trying to turn the plate by hand. If the plate turns freely, its the drive sleeve. If there is a lot of resistence, it's the motor.
The reason I say that the worn out sleeve is the most likely culprit is that there appears to be a design / manufacturing flaw in this oven. The placement of the motor, the length of the motor output shaft and the length of the drive sleeve were not coordinated. As a result, the motor shaft only partialy engages the sleeve. This means that the torque from the motor is transferred through a very small portion of the sleeve, causing a very high contact pressure and early failure of the plastic parts.
You can see what I'm talking about by removing the turntable and prying up the drive sleeve (don't loose the teflon washer that is between the sleeve and the floor of the microwave). Examine the end of the sleeve and you will see that the hole in it is 'D' shapped, but at the very end of the opening, the hole is rounded out (the flat part is now rounded).
A new drive sleeve will solve the problem, but only temporarily, as the same thing will happen again, unless you get a replacement motor with a longer output shaft to more completely engage the sleeve.
I temporarily solved the problem by carefully grinding away some of the plastic on the flat side of the hole and then installing a thin metal shim to restore the original 'D' shape. Because of the engagement problem, I don't expect that thi fix will last too long.
I have an inquiry in to Panasonic on replacement part(s) and I will post the information when I get it.
Eric May
February 2008
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