My passenger side 3rd row seat would fold flat but not come out. Found a great article here: https://www.justanswer.com/chevy/52u...row-seats.html

Although that wasn't my issue, drilling the hole on the inboard side of the seat on the back trim panel did allow me to reach in and push the release lever as described in the above link.

My issue turned out to be one of the cables that connects the level by the removal handle had come out of the connector. Once you get the seat out and remove all the torx screws holding the trim in place around the bottom of the seat, its easy to find the issue. I was able to easily remove the connector from its location, and placed it in a vice. Used an awl and hammer to open it up enough to re-insert the cable. I used a pair of bolt cutters (carefully) to re-crimp the connector as I didn't have access to my crimper. Put everything back together, and the seat now works as designed.

The hole in the above picture doesn't need to be quite as large as shown - i used a camera scope (illuminated) to find the lever to push once I drilled the hole.

Just sharing in case someone needed a hint.

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