I found several threads about the driver's door soft close function, but not much otherwise.
Three of my four doors soft close correctly. The passenger rear door does not soft close. It functions perfectly fine otherwise, like a normal car door. If I barely latch the door, nothing happens: no noise or indication that the soft close attempts to operate at all.
I have been unsuccessful at getting SDD to run a diagnostic on it.
Before I pull the door apart and start poking around hoping to find something, are there any tips or suggestions on what to look for?

 

Search " soft close door repair " and you will find all the help you need!

 

And yet I didn't, which is why I posted. There's one big thread: most of it's about the driver door, and a couple posts about the broken plastic gear. I don't think that's my issue, as I do not hear the actuator running when I half-latch the door.

 

One of the reasons I bought a 2011 vs newer.

Some of those convenience features that were added won't age well.

Unfortunately, they do seem to help sell cars to those that will never be concerned with repairing them.

 

Time to pull apart the door. I would imagine there is a microswitch inside the latch mechanism that triggers a "close" event. I would also imagine that dirt or grease could render that switch inoperable and you may be able to probe around with a multimeter to confirm this (unplug so you don't send current upstream to the control module).

 

Well you say there is no noise and that was the key when one of my doors stopped working. I had the broken plastic gear your talking about.
Here is my thread but it does seem to be different than what you seeing?
Soft Close Broken Plastic Gear

I would take the door panel off and then get in the car and watch what is happening with the suction motor and cables
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