Bench test 8 pin window motor?

I have replaced the window motor, and it would not turn the gear. I can hear the motor trying to run, but it doesn't move the gear. I swapped it out, luckily the warranty let me swap it for another motor. The second motor did the same thing. I have swapped it again for a third motor. I suspect that it may not have been a faulty motor as it is not really likely to have received two faulty motors back-to-back from the parts store. Before I install the third motor, I wish to bench test it. I know that a two-wire motor is a simple positive to negative situation. The motor I am swapping is for the driver's side door and has an eight-wire setup for auto up, auto down, etc. My question is, do I need to do anything additional to test the 8-wire motor, such as provide extra grounds on all ground wires or put a voltage to an additional wire to get the motor to move? Or do I just need to supply a voltage and ground across the pins for the motor itself?