1.Disconnect the harness coupling from the motor.
2.Insert a test light probe into the coupling and clip the ground wire of the test light to a good ground.
3. Turn on ignition switch.
4. Now operate the window switch. The bulb in the test light should light up. This will establish wether or not you have power to the motor. If the bulb does not light up, then you have no power to the motor.
5. If you don't have power, check the fuse for that circuit.
6. If you have established power, then either the motor is bound up by the regulator cable or the motor is just worn out.
If in fact the regulator is good and the motor is bad, it is still easier to pull the regulator out to get to the motor. You might need a Torx driver to pull the three screws that hold the motor to the gear sector. Hope this helps.