Has anyone gotten this "Cancelled. Trailer jackknifed." error when trying to use Advanced Tow Assist?

Process/Symptoms:

1. I'll select the Advanced Tow Assist icon
2. The screen repeatedly displays the "Apply brakes and shift into reverse." message for a moment and then says "Cancelled. Trailer jackknifed." It toggles back and forth between these two message 3 times then exits.
3. During that time I can select the "Start" button and when I do I get an error gong sound and it says Cancelled then exits
4. If I try that 2-3 times it eventually asks to calibrate the trailer. I'll go through the calibration process of driving straight forward, which seems to be successful.
5. Back to step one with no change in behavior.

I've deleted my trailer profile and re-entered it several times and also made sure to do the calibration in a well lit area without shadows.

My Tow Assist 2 activation was done by Ralf Sarek, when I asked him about the error he said he had seen it before but couldn't recall what the solution was. Can anyone point me in the right direction?

 

Following this thread, My 23.5 came with this option as I bought from the dealer lot. Imo seems like a waste of a $1800 option.
Wish I could sell it! The option that is, Lol

 

Is your trailer mirrored / ie stainless steel mirrored finish?

Edit: never mind, it's not a closed trailer, is that right? I was wondering if all the trees in the image were screwing up the works.

 

It's an aluminum open trailer. The finish has typical aluminum oxidation and is not reflective.

That is a good point about the trees and shadows. I did try it in an open area with the same result.

 

We have Advanced tow assist and when the vehicle was picked up it had a sheet with an adhesive back that looked like this:




It measured about 1 foot square. No one at the dealership knew what it was for, and it got tossed. Subsequent investigation indicates that prior versions of tow assist needed to have this decal stuck to the front of your trailer for the system to calibrate itself. We have periodic problems when the trailer is "not recognized" and have never been able to identify the problem. I am now wondering if sticking a decal like this to the trailer might help both @MickD and me...
Anyone else had experience with these decals?

 

I was under the impression that newer models don't use that sticker but it's worth a shot. It would be simple to recreate once we have the dimensions.

@sarek did you ever recall how you resolve the "jackknife" error in the past?

 

So my asking this same question to LR Portland in early 2021 eventually yielded the answer from the service Dept that the 2020+ defender w/ advanced tow assist does not use the circles on trailers. It automatically does it. I think the deal is that they were on the trailer equipped pre Pivi LR models. My dealer of course had no idea about this and took awhile to suss it out as it was a new product to them at the time. That said I've had 2 trailers hooked up to mine w/ advanced trailer assist, no circles, with the auto calibration (you just drive for a distance straight or something while it's active -- it tells you what to do).