2003 Past Wagon 1.8T. The driver's seat started slipping and will not lock into place. Is the mechanism broken or maybe just loose. 20 lb. rock in back floorboard is keeping the seat from moving temporarily.

assuming you mean the seat is broken on the frame and not moving under power, remove the seat, fix (weld?) the frame or replace it.

It's a power seat or manual?

ratchet broken or loose on side of seat.

The adjusting lever for seat position is not locking into place. On the bottom of seat are runners on each side with holes in them that the adjusting lever tabs will lock in and hold seat in place. The seat slides on the runners if those tabs are raised. There is also a connecting wire or rod from the lever to the other side of seat so when lever is pulled up, tabs on both runners are raised for seat to slide. Something is keeping the tabs from locking into the holes on the runners in your car. Maybe the adjusting lever is broken somewhere, or the wire/rod came loose, or the lever is just dry and sticky and needs a shot of WD40 to loosen it up. If you can't see it and fix it with seat in place, then pull the seat back off for the repair. Good luck. Post back if my explanatiopn is not clear or you still need help.

I just got done fixing mine. The culprit was a slipped axial spring by the key-lock mechanism in the seat. Yep, it's likely that nothing is broken, just a bad design, I'm looking at you MINI. It's not pretty to get at, but the repair is fairly straightforward.

Labeled pictures can be found here: http://www.flickr.com/photos/25717593@N04/sets/72157629775433188/with/7217494500/

The first task is getting the seat back out. I tried several different ways to "alternatively actuate" the latch from the back, but couldn't see anything and couldn't come up with an appropriate tool. The nature of the failure doesn't let you grab the cable with pliers and pull. The cable is totally useless at this point.

So, I went in from the front. To get at the latch mechanism, you have to partially pull off the upholstery. Luckily, it is not nearly as bad as it sounds. The upholstery has a plastic edge that presses into a seam on the back side of the seat pan. You just start at the top of the seat, and start pulling the edge out. You can do it with just your fingers. I'm afraid as time goes on and the cloth gets worn, things may rip, but my '05 interior has held up quite well..... even in AZ. Anyway, separate the edge as much as you can from the top, around the upper right corner and down the right side. Maybe you can get away with just pulling away the top.

Pull back the top and right corner of the upholstery and padding. Again, maybe you can get away with just pulling away the top.You just want to get enough access inside the seat to see in at the top left corner with a flashlight. What you'll see is a metal ear with a hole in it. Take a coat hanger, put a small hook in the end, fish it into the corner, hook the hole and pull the ear up. Your seat will unlatch.

Once you have the seat back removed, pull back the upholstery from the upper left corner and remove the two Torx bolts. Bend back the upholstery, hold on to the plastic key lock housing from inside and pull it straight off the latch assembly. There are no screws hold them together, its just a press fit of plastic onto two posts.

You can now see the top where the cable end is attached. You will see the axial spring and it will more than likely be resting on the metal housing instead of the plastic lever where it should be. I just put the spring back on which is dumb because this failure is bound to occur again in the future. If I have to do it again, I will probably heat up a small piece of pin and push it into the plastic behind the spring flange with it sticking up about two spring wire diameters. This would act as retainer and probably keep the pin from wiggling off again.

Look at the annotated pictures linked above for more info. Good luck.

examine the seat belt lock. maybe the spring is broken or stuck up

my 99 explorer was on a recall for the same thing and they fixed it for free like 8 months ago

Parts have come loose in that brake area. Pull it apart and they will fall out. More than likely the hand brake mechanism has slipped out of place.

I have a corolla 2003 and I had the same problem. I turned the key to the left and the lock turned left, engaging the valet parking mechanism. I could not turn the key to the right and could not get access to the trunk because the lever next to the driver seat was disengaged.
The way I solved this problem is as follow:on the back driver seat I pulled the back seat forward to leave an opening and snick my arm in the trunck. Then I grabbed the cable used to latch the seat and I pulled forward, i.e. toward the front of the car. The cable is connectred to the trunck so that it can be disconnected easily if pulled towards the front. If you pull towards the back it will remain attached to the trunck. So grab the cable an pull towards the front, and it will release itself. Since the cable is flexible, you can pull it out of the trunk from the same the opening you put your arm, and then disenagage the driver back seat. Fold forward the back seat and get into the trunk and use the lever in the latch of the trunck to open it. The turnk will open.

If the lock does not turn, you need to disconnect the lock from the mechanism, so that the driver seat lever can start working again. To do this, and with the trunk open, remove the cover holded by nine plastic pins. Do not break the pins. After removing the cover, you will see the lock holded by two nuts. Remove the nuts with a rachet. The lock will be loose, and disconnect the lever that connects the lock to the latch. At this point the driver seat lever will start working again. Close the trunk and verify that the driver seat lever opens the trunk. Now you can open and close the trunk , and have time to call the dealer for a new lock.
Good luck.

its the dreaded seat rock syndrome, plenty of fixes on the forums, basically you have to replace spacers in set drive mechanism. I did with the help of a friend after ordring bushes and it was quite easy.