mercury help!!!

i am working on a 96 mercury mystique. the car has power everything. the prob. the power window on the pass front goes down but not up. i changed the motor 3 times the switch 4 times. ugh all did the same thing. i was told it could be the master switch in the drivers side door. when i use the switch in the passenger side door it goes down but not even a sound when i push to go up. now when i push the button on the master switch for that door absolutely nothing happens, but all of the other doors work fine. and also i need to know there is a 2 prong plug that plugs into the motor i dont know if one wire is positive or both or reversed. any help would be greatly appreciated. i am not very familiar with the newer fords,. thanks rockfangd@aol.com

As far as the motor, if the wires were reversed on a 2 wired motor, then when you wanted it to go up, then it would go down. Wanted down, it would go up.

I would say the best thing to do is use a volt meter and trace back. Check for voltage on the out of the switch, then check the volts on the in circuit of the switch. Start from the motor, and work backwards.

does anyone know what the connectors are that plug in. i dont know which are positive and negative