I have a problem with the back widow. It rolls down when I turn the ign. key off

What a strange problem. The power is coming from somewhere, and it will take a little bit of work to find out where/why it is coming from. If you have already inspected everything you can, it is best to have a professional take a look. That really is an odd issue. Link below is for certified shops in your area, but in the mean time, try this: Get in the vehicle and close all the doors and roll down all the windows. Then, remove and reinsert the key into the ignition, and turn it to the on/run position without starting the engine. Close the window with the switch on the driver door, but don't release it until the window is all the way up AND the key has been removed. Now exit and lock the vehicle as normal. If that doesn't work, click here for hands-on help: http://repairpal.com/nissan-within-10-miles-of-hico-texas-76457