66 new yorker 4 door rear window motor acting up


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Mar 28, 2015
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I have a rear window motor that will not go up either with the master drivers door switch, or its own switch, I have the assembly out of the car and have verified the motor is good (it is a newer dorman motor) it will roll down, not up. The switch and its connector seem clean.
If the motor will run one way, it should run the other way. The directional rotation of the motor is changed by reversing the flow of current into the motor, this is done thru the switch. If you reverse the polarity of the leads gong into the motor, its direction should reverse as noted above. If the motor runs using this technique, the motor is fine. Check the wiring to it. If this car sat for a long time, sometimes a door can become ungrounded because of corrosion. Doors are grounded thru the hinges, if they are rusty, that could also be your problem.

The car is daily driven, this motor works fine in the other rear door/switch up and down. It was working perfectly prior to this, it just wont go up now.
Have you tried swapping one of your other single switches? They are all the same.

If it still is inop it just might be in the master switch. The ground for each motor runs back through each individual switch on the master. I have seen cases where the toggle for one of the windows does not fully close, losing the ground for only 1 motor.
I have swapped the single switches into the other rear door it works fine there, i am leaning toward the master switch as well.