The coupler teeth are likely damaged or disengaged.
DIAGNOSIS: Probable causes: removing the jar while spinning, or pushing down on the lid during operation.
FIX:
- Ensure the blender is unplugged.
- Do not force the lid or jar.
- Support and lift the blender from the base only to inspect the coupling mechanism.
- Align the jar handle towards the control dial and fit it into the jar pad slot.
IF THAT DIDN'T WORK: If the coupler teeth have come off, the unit requires professional service. Contact KitchenAid.
HEADS UP: Always carry the blender by the base, never by the jar or jar handle.