Start by reconnecting the wiring to the Power sliding door. Remove the PSD-15 amp fuse for 30 seconds. Reinstall the fuse, then follow the steps below to reinitialize the door module.
Also try cleaning the contacts at the leading edge of the power sliding door and the door jamb. You can use a Scotch-brite pad or steel wool.
Let me know if this works for you or if you need further assistance.