I have searched the internet and YouTube to find out how to fix my Toyota Sienna XLE 2006 sliding door problem. They were time consuming, high risk, and more expensive. My method is cheap, about $4 ($6.70 after tax and shipping in Minnesota) each door and it took me less than an hour, seriously !!!
My method is pretty generic, it may apply to other car models.
Step 1: Symptom of Sliding Door Latch Problem
When you press a button to automatically open the sliding door it makes noise attempting to open the door but fails. But if you pull the handle and hold it for a few seconds the door opens.
The sliding door latch is not working (see the picture of the latch unit). The door is supposed to unlatch first before it triggers the motor to pull it open. Most common problem is the motor of the latch fails.
My simplest solution:
Replace only the motor of the latch instead of the entire latch unit.
Step 2: Open the Inside Door Panel
What other people did:
There are many resources such as YouTube of how to open the inside cover panel so I will not go into detail here. What other people do is removing the cover panel then remove the inside metal panel to gain access to the latch unit. It's time-consuming and many things could go wrong. After removing the metal panel, it is still not easy to remove the latch because it uses non-standard fasteners. I saw on YouTube people struggled with removing the latch unit.
Only partially open the cover panel, lift its bottom up and use a box (or anything) to hold it up. No need to remove the inside metal panel.
Once you partially open the cover panel you will see the latch (see the picture).
Step 3: Replace the Motor of the Latch
I used a rotary tool (1st picture) to cut open the latch where the motor was (2nd picture, red circle where the motor is).
The 3rd picture shows what you see after you cut it open, the motor of the latch. The 4th picture shows a closer look at the motor. Remove the motor. The 5th picture shows the cutout piece of the latch.
The label on the motor shows the part number (6th picture). In my case the part number was PAN14EE12AA1 for Toyota Sienna 2006 XLE, I ordered it from DigitKey for $6.70 (after tax and shipping) for each door.
After getting a new motor, insert the motor back. You may need a magnifying glass to view the flat side of the motor shaft. Align the flat shaft of the motor and insert it. The motor has two electrical plug-ins, they should face outside.
I used a hot glue (7th picture) to glue the cutout piece (5th picture) back to the latch.
The last step is simply put the cover panel back and you are done. I finished it in less than one hour the first time, the 2nd time would be even quicker after knowing exactly what to do.