2005 Toyota Sienna sliding door problem

Check to see if there are any restrictions in the door track. If the sensors feel any resistance they will stop movement or reverse it for safety reasons. There could also be loose connections in the door wiring loom.

Could be resistance in one of the tracks, or the motor.
If the motor hits a resistance the door opens in case the resistance is a human.

See if power reaches the motor. If it does and motor does not operate you have found the problem. If no power then the issue is electrical in nature and you will have to trace the current flow to the motor.

Try this... it fixed my problem whereby the 2005 Toyota Sienna passenger sliding door would sometimes open and sometimes not, yet I could hear the motor trying to open/close it. It cost me 20 minutes and 10 drops of oil, not $1200.

First, get the door open. It took me two weeks of constant trying, but it finally opened.

Next, remove the plastic covering of the inside door handle this way: locate the two screws on the forward edge of the sliding door near the child-safety switch: (the switch is a small lever near the door latch, on the forward edge of the door) loosen and remove the two phillips screws, one above the child-safety latch, and one below.

Remove the plastic cover to expose the gears for the door open/close mechanism.

There's a bunch of intricate plastic and metal parts in there, all coated with white grease. I used some 3-n-1 oil to lubricate everything in there thoroughly, In my case, there was one part that was a little void of grease, hence it "stuck" occasionally.

Test the system. If it's Okay, replace the plastic cover, and re-install the screws.

Now my Toyota Sienna 2005 door never fails to open or close.

I got this problem with my 2001 Sienna too.
The Toyota deal said the computer BD is bad.
They charge me about $350 to replace with a new one.
However, the new parts is in shortage.
They said lots of back order for it!

Check out the wiring. Sounds like something is loose or the switch may be going bad.

To start, the noun "''rear latch switch'' is incorrect. It's actually called "Slide Door Lock". It's located on page BO-20 of the Toyota Repair Manual for the 2001 Sienna. There are two door locks on one sliding door. One in the front and one in the rear. Obviously, you want the one in the rear. The location for the "Slide Door Lock" (which also contains an electric switch) is in the rear of the sliding door located mid way up door. You can see (sliding door opened from the back) it without dissembling the door. And, the lock is made up of plastic (dirty white in color).

This may or may not work depending on exactly what is wrong with the door, I cant tell what is wrong without looking at it directly however:
You can try starting with all doors closed and unlocked, keys in hand disconnecting the battery and letting the vehicle sit for 2 min or so, then reconnect the battery. Put the key into the ignition and turn it to the on position but do not start the van. Next press the button to disable the power sliding door for the drivers side, then manually open the door fully, wait 5 seconds, then close it manually fully. Press button the button again to re-enable the power sliding door, then try to use it with the automatic feature either by pulling the handle or using your remote, this may or may not work depending on if the door has somehow become de-initialized (it should work now) however if something is broken inside the door closing mechanism or door closed/open sensors, the door will continue to malfunction.

The suggested fix above did fix my problem. The problem is that a 2.5" hinged finger that pops up from the floor of the door opening to block the door. Apparently, the finger should, but doesnt go back down after the gas flap is closed. Even after I got hinged finger down (so that the sliding door would open/close all the way), it still would not go back down after the gas flap has been opened. i.e. I have to push the finger back down every time after we fill up with gas. It looks like there is a little wire/spring that should pull the finger back down, but it is off of the finger. I think that replacing this back on the finger should fix the problem permanently.