OK folks, here's the scoop!
I just finished swapping out the motor/drive shaft/worm gear assemblies in my 2001 Pathy front driver seat. Had the typical problem of getting stuck with the seat all the way back, the right side moving incrementally back and forth with the left side immobile. Pushing seat, pulling seat, tapping motor - zilch. I've lived with this for a few years(!!!) as I'm tall, but my girlfriend and I are going on a long trip and I wanted to get the automatic seat positioning fixed as well. So from the forums (rock on!) I found the link to the technical service bulletin (TSB) for this.
http://www.justanswer.com/uploads/fixur ... 0-095a.pdf
I ordered the part listed in the TSB, Seat Slide Motor Kit 87562-C9925. About $280 to the door (Ouch, but forget about going to the dealer!). Came with new motor/drive shaft/worm gear assemblies. ****{One caveat, this TSB applies to Pathys with "Automatic Drive Positioner", i.e. those little buttons on the driver's door, about even with the steering wheel.}**** Not sure if there are TSBs for other door systems?
The TSB was awesome. Here are some pointers:
1) If your seat is all the way back, you need an 14 mm angled hex wrench to get at the rear bolts, because the brackets for the rear bolts don't allow access for a regular wrench. You'll see what I mean!
2) Make sure the seat back is angled all the way forward before you unplug the connectors, and tilt the steering wheel all the way up. The seat comes out the driver door, and it's a heavy sucker.
3) Unplug battery terminals for 10 minutes before unhooking electricals. Something about not activating the airbag....! For the connectors, the two smaller ones to the left have release tabs on the passenger side, squeeze and pull apart. The large white connector has a push tab in the middle, and the yellow connector has an internal tab on the end that you depress with your finger tip.
4) Dis-assembly per TSB, need 10 and 12 mm hex wrench and phillips head screwdriver. The four 12mm bolts securing the seat to the frame were torqued pretty high, so I had to use an extension rod on my torque wrench to loosen them.
5) Assemble in reverse order. Make sure the drive shaft connecting the motor to the left worm gear housing (oriented as shown in the TSB) is properly seated at both ends (square pegs/holes). Each worm gear housing has 3 bolts that go through the seat frame, and if the drive shaft isn't properly seated then the bolts won't slide in easily.
Seat now works like a champ, and I can reset the ADP for my sweetie and me.
So those are my main points, but this is my critical observation about the whole design problem, assuming that pushing and motor tapping don't work for you. The worm gears turn long threaded rods that run parallel to the seat sliders. The seat slider connects to the rod (1 bolt) via a small box that acts as a moveable nut on the rod. The motor turns the two worm gears/rods, moving the nuts (and the attached seat) back and forth. The slider rails are separate from the movement assembly, so the issue is not with them. What I've read from the forums is that the seat gets "stuck in a rut" when the seat is "back". In reality, when the seat is back, the large nuts on the rods are up close to the front of the seat, i.e. nearest the worm gears and motors. No "ruts" my friends. So what stops the large nuts from moving all the way to the front of the rod and hitting the worm gear housings? (wait for it....) A small nut assembly on the rod about 1 inch from the worm gear housing, but only on the rod on the motor side (left or driver's door side when seat is installed)! Eureka! So when the seat moves back, both slider nuts move forward, until the left nut is stopped by the small retaining nut unit. What stops the right side nut from moving? Nothing! So the right side continues forward a bit, yawing the seat. If the two rails become sufficiently out of alignment, I'll bet anything that the motor can't deliver enough torque to unwedge it, hence the success of the "pushing" posts. The other very real possibility is that as the seat yaws, the skinny little drive shaft gets disconnected from the right worm gear housing, in which point the right side will stop rocking back and forth completely. From this, if I were going to push anywhere, I would push the FRONT of the seat on the CONSOLE side to the REAR, while activating the switch.
What's my solution to all this heartache? One I wish I had thought of when I did the replacement. When the replacement parts are just out of the box. put another retaining nut unit (could take from the old part) on the 2nd rod, and tighten it the exact distance from the worm gear housing as the preexisting one on the rod near the motor. That way, both slider nuts are stopped simultaneously, no excessive movement of right side of seat, no wedgies, no disconnected drive shaft, no motor burnout. If the problem comes back for me, I'll pull the seat immediately and place the 2nd retaining nut unit.
My other advice would be that if the seat still yaws on the right, then the motor is still working, so you may not need a $280 part. Disassemble the seat as in the TSB and reassemble, making sure the drive shaft is seated properly. And add a second retaining nut unit to that other rod!
Also, as an added bonus for reading this massive post, it looks like the rod retaining nuts could be moved up a bit giving the taller folks among us a little more legroom, but this is highly speculative.