Model fwx833as1. I did not witness the problem develop, but found a dry tub (pump worked) and a functioning motor. On inspection, the agititator/tub will not rotate counterclockwise as the motor rotation would indicate. Belt is properly adjusted and slipping against what appears to be a locked transmission?

Don't want to attempt testing wash cycle because filling the tub would be a problem for removal if the pump will not drain it (very cramped location up some stairs)

How can we verify the problem without a service technician?