Trackpad works at login but not after boot
I have a Macbook Air that is a customer's, given to me with water damage that seems to have affected the display (only visible issues), as well as the trackpad and keyboard. However, after investigation and a replacement of the trackpad which seemed fully nonfunctional, the trackpad and keyboard now fully function on the login screen but fail to respond once reaching the desktop.
OSX asks if I want to setup a bluetooth keyboard so I know it is fully not recognized. I also have reinstalled OSX in order to try revitalize the situation but to no avail. Is this is software issue or still potentially hardware??