This will get you to the dealership without going insane from the door alarm chiming through the car's radio speakers. They need to repair this for you. It is expensive.
Our Terraza sliding rear door stopped working. It moved very easily, like it was not pushing against the normal resistance in the mechanism. It would pop the door open, and it would latch closed manually, but it would not slide itself open or closed. It made the normal "i'mopeningyourdoor" humming noise, but the door did not slide under power. For a few moments while it tried to open it would stop beeping but then the door would figure out it was not doing right, and start the chime up again.
The door thinks about itself. When it stops beeping and starts trying to move, it is waiting for itself to do right. It notices it does not work and starts the incessant chiming alarm up again. What you need to do to get it to shut up is disconnect the motor AFTER you push the door-open button, WHILE it is trying to open the door, BEFORE it starts beeping again. There are two connectors, and they latch in place on the motor. You have to be quick at this.
The motor is hiding behind plastic trim panels, right beside the rear seat. The passenger side is easy to reach in our terraza, just open the access panel where the jack is stored. The driver's side would require pulling (just pull, I think there are no screws) the plastic trim panels off. If you are reading this, you know that you will be ready to flip the whole car upside-down to get the thing to quiet, so pulling the trim off shouldn't be too hard. Expose the motor. Push the door operator switch. Pull off the two connectors going to the motor. It should stay quiet if you timed this right. A helper is probably necessary
The mechansim in our van is obviously broken. Carmax already replaced it once under warranty. Here's hoping they will again.
My Darling Wife reported a popping noise before it stopped working. The popping noise was the cable snapping inside the mechanism, or the mechanism breaking.
Bonus poor design workaround information
If the door will not stay closed, the weatherstripping on the bottom of the door opening is probably loose. Push it up back into place. If it still will not closed, you may have to force and lock it manual. This is bad but if you need to do it to get home, do it.
If the door will not open, unlock it from the inside manually and try again. If it still will not open, leave it closed and make an appointment at your dealership.
If there is a wire or cable hanging loose from the slot in the outside of the body of the van. If there is a crunching noise from the back by the seats, behind the plastic. If it can't seem to tell that it really is open or closed. If manually operating the stop switches makes no difference . . . make an appointment at your dealership. This mechanism could have been designed better, but at least it is repairable.