I have a Carrier FB4CNF060 heat pump unit and the blower motor cuts out about ever 3-5 minutes. The motor has been replaced and still same problem. The unit doesn't seem to have a main circuit board, the motor is definitely getting proper voltage. The leads connect to two small circuit boards with resistors on them. The motor wiring diagram does not describe what these boards are. The unit does this whether it is running in AC or Heat mode. Any help on this is greatly appreciated.