The motor windings have failed. It needs the motor replaced, so it will need to go to a repair center near you. You can find all the information you need from their website.
Either the coupling from the motor with the fingers on it is not really attached to the motor shaft or the drive on the blade that engages with it is not attached to the blade shaft. One other thing is that on some models if the rubber jar seal between the beaker and the blade carrier is in the wrong place it can raise the blade drive to not engaging properly with the motor coupling. The gasket goes between the jar and the blade carrier, not under the blade carrier.
the top rubber piece could be worn enough that it is not engaging the pitcher. look at it carefully and see if the "teeth" of the rubber disc on top of the base has not cracked and worn away. a picture of the new one can be seen on the parts websites to compare I spent $10.00 for my replacement but i found them at other sites for $6.00. you will need a very skinny 7mm open ended wrench to get the old one off and it is left handed threads that means clockwise will loosen not tighten the part.i ground down my wrench but an ignition wrench from an auto store will usually be thin enough to reach the flats on the shaft under the rubber disc
there is a voltage regulator inside the circuit board , this might have got wet some how . this circuit controls 1-10 speed from a touch of a button . will have to disassemble unit , Auth personal should check this , unless you know electronics
If it is the motor (quite rare), these people may be able to order you one: http://kitchenaidblenders.co.uk/Home/tabid/36/c/KitchenAid-Blender-Spares/CategoryID/6/Default.aspx
This is a common problem. This usually happens when either A) too many ingredients are added to the jar or B) the blade spokes do not sit properly in the coupling (the rubber piece). The coupling can be replaced easily. There is a great video on Applianceinsider.com on how to take the coupling off as recommended by KitchenAid themselves. The part can be found at 1800parts.com if you call them their reps are extremely knowledgeable and will be able to help you find the part in seconds. Or if you have the model number you can locate it right on their site.
Actually the drive gear was vulcanized onto the shaft during the production. If you can get glue to hold it on you're all set but I think you'll end up replacing the whole blender soon. Thank you, Dana
