I removed the upper portion of the back seat and found that the working side looked to have something more than the non working side. On the passenger side(the non working side) there seems to be only one unit and a yellow wire running in that portion.

The working driver side has two units and no yellow wires.

http://www.exigencies.org/passenger1.jpg
http://www.exigencies.org/passenger2.jpg
http://www.exigencies.org/passenger3.jpg
http://www.exigencies.org/driverworking.jpg