Clearly the motor control is ok, as the drum operates as normal - so it can't be the triac or brushes or control circuits. Most / all modern washers have a spin inhibit to avoid damage - this is normally based on a) water in drum - drum must pump dry within fixed time so check pump filter, outlet hose - can you hear the pump change speed as it starts to suck air, and is outlet hose showing good rate of waterflow, is main drum to pump hose blocked by coins, hairgrips, small objects + hair, b) water in drum (check that the level sensor (a sensitive air-pressure switch connected by hose to bottom of drum) is ok, c) final spin speed selection has failed - output of digital switch or variable resistor. Vary rarely the older electro-mechanical controllers failed.
MD, December 2006