Have you checked for an open and measured resistance as I mentioned before by unhooking the switch?
Just in case you missed that post here it is:
If I can jump in here. This system is applying voltage to one side of the motor or the other to dictate direction. If you don't have a complete circuit from the switch to the motor on both wires then you will have an open circuit and no voltage. In other words, looking at the diagram, when you press the switch to the down position, it sends voltage on the brown wire to the motor and then returns on the blue wire to the switch and then out to ground to complete the circuit. Then backwards on the up position, out on the blue wire, the motor goes in the other direction and returns on the brown wire and out to ground.
I would disconnect the window switch and measure resistance between the brown and blue wire from the connector to the driver motor, leaving the motor hooked up. I suspect it is open which is why you are not getting any voltage. If it is, then unhook the motor and ohm out each individual wire. If each wire by itself is around a half ohm of resistance then I suspect the motor has an open in it.
If you really want to confirm this, then jump 12 volts to the motor to confirm what you are seeing with the other test if you find the wires are okay. Clearly you will need to jump 12 volts to one side and ground to the other and do this with the connector unhooked. Do both sides just to see if it will move in either direction. Basically you are running the motor separate of the rest of the system.
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Tuesday, April 7th, 2020 AT 7:14 PM