HI:
I may be way out in left field but it is possible there is a loose connection to the touch pad.
Has any one opened this device up? have you dropped it ? The touch pad is a separate device on the new laptops and has a separate serial connection to the motherboard apart from the keyboard or could be run in the keyboard connector, (have not had any of your like machine apart).
I have seen a well used unit have the cable squished because of constant pushing or this one fellow kept his paper note pad wedged in that got the thing partially broke from pressure not intended at this area or any other area.
Also as devices go they last longer than the laptop but you may be the unlucky person number 89 with a defective pad.
Yes it should be in the list of connected components because it is a separate device.
So either learn how to take the top off and look at the wiring or order one from e-bay and enjoy replacing it. I would guess a repair shop would charge for your laptop repair worth a big bill. I turn mine off and have a wireless little mouse. Cant stand playing with the touch pad, always resting my palm or fingers on it and away goes email or new browser windows or pointer flying some place while typing.
Just me you know...
Good luck
Alton