Saab,Loss of voltage at blower motor when it is connected to regulator

I have a complete loss of voltage when I connect the blower to the resistor – resistor, blower brand new – blower works when attached to battery, voltage at the resistor is between 10.7 and 12.5 when car is running but as soon as I attach the blower motor to the resistor, it drops to zero. Tried connecting blower direct to wires from switch, which had voltage, bypassing resistor, but the voltage still drops to zero.
My car has an automatic transmission.