Let me try to take a stab at an answer.
You are setting your meter to ohms, to check for a good switch, but checking from the motor to ground. Not something that is needed right now.
Try this, if you have a digital meter:
With the connector shown above on the motor unplugged.
1. Set the meter to DC Volts.
1.1. Might be a V with a dashed line over a solid line, like an equal sign.
2. On the connector towards the switch
2.1. Put the red probe on one pin
2.2. Put the black probe on the other pin.
3. Turn the key on
3.1. press the window switch down.
3.1.1. You will see either:
126.96.36.199. + 12 V ( or 12.6 / 13, depending on the state of your battery, but something more then 10 V )
188.8.131.52. or - 12 V DC.
3.2. Press the window switch up
3.2.1. You will see either ( but the opposite reading from 3.1. ):
184.108.40.206. + 12 V
220.127.116.11. or - 12 V DC.
3.3. Turn Key to the off position.
3.4. Set meter to ohms ( or might be the Greek omega sign )
3.5. place the red probe on one of the 2 pins in the connector towards the switch.
3.6. place the black probe to the body bolt you used to get 4 ohms before.
3.7. you should see less then 10 ohms
3.7.1. This is checking the ground supplied from the driver's door.
3.8. place the red probe on the other pin in the connector towards the switch.
3.9. black probe on the same body bolt.
3.10. you should see less then 10 ohms
3.10.1. This is checking the ground supplied from the driver's door, on teh other side of the switch.
If both of these are less then 10 ohms, the ground supplied to the motor is good.
If you do see these readings, there is a problem with the motor, as the switches are supplying voltage to the motor, the motor is just not moving.
4. Confirm Motor Operation
4.1. On the 2 pin connector TOWARDS the motor, connect a pos lead to one side, and a neg to the other side.
4.2. If the cab lights dim, and nothing happens, reverse the leads ( you were trying to push the window up more, and the load was seen ).
4.3. If you reverse the leads, and the cab lights dim, and nothing still happens = bad motor I would say.
Give that a try and let us know what you come up with.
If you do not get voltage in step 3.1 or 3.2, there is some more checking to be done on the switch, and the circuit, but that is a bit longer post I'll wait on, to see if you need it.