2011 LT:
Drivers headrest will not go up or down. Passengers headrest works fine. Based on observations, it might have been built wrong from the facxtory??

Reference the pictures.
The drivers seat left post has the release button but it does not move. The release button looks like it is already pressed in because the button is flush with the base. The shaft also does not have notches.
The drivers seat right post has notches but does not have a release button.
The passenger side works fine. The release button extends over the edge of the base and the shaft has notches. The other shaft has NO release button and NO notches.

Drivers seat. Left shaft, NO notches. Release button looks already inward because it is flush with the base.

Drivers seat. Right shaft, Notches, NO release button.

Passenger seat. Left shaft, Notches. Release button does not engaged. It extends out passed the base.

 

Somebody put a right side headrest on the left side.

 

Sumthin' strange here.

 

I believe Firemangeorge has the correct cause.

If you look carefully at the outer part of the right post base, you'll see a tiny slot. Push a tiny flat screwdriver (or equivalent) into the slot. While holding it in, lift the headrest until it stops. There is 1 notch in the left post, push the left button, and you can now remove the headrest and reinstall it the original, factory installed, position.

Or you can just adjust the height with the screwdriver and leave the headrest backwards.

 

Mystery solved. Remember this is my wife's new ride. She bought and installed waterproof seat covers front and rear to preserve the still perfect OEM seats. When she reinstalled the driverside headrest, she installed it 180 degress out of rotation, thin side to the front.
Pop it out, rotate it and rotate the cover 180 degrees. Done deal.

Thank you.