The Victor might need to be calibrated then.
Page 2 of
this.
No, strike that. The Dashboard PWM indicator could only be fooled by the joystick input.
You can take the joystick out of the loop temporarily by changing the Motor Set Speed to use a constant (1=full backwards or -1=full forwards).
Since the window motors probably attached to something, you can pull the breaker for it and just watch the Dashboard PWM indicator to see if it goes to full.