Connect battery positive voltage to terminal A and ground to terminal B of the blower motor and verify its operation.
Mazda 6 Service Manual: Exterior lighting system
...
Mazda 6 Service Manual: Rear drain hose installation
Caution
If the rear drain hose is pinched or bent anywhere, the water in the hose may
not discharge and enter the inside of the vehicle. During and after installation
of the trims and the headliner, always make sure there is no interference with
the rear drain hose. Fix any problem if foun ...