eah I have tried everything also. I get no honks at all when it starts and it doesn't learn the sensors either. I can let out air or add air for 20 seconds and it never moves off the first tire. I tried just letting out air for 10 seconds on each tire during the 2 minute learn time hoping that it would honk twice after the fourth tire or learn all 4 and I would see it on the screen. I'm at a loss. Don't know what else to do. I'm trying this on my 2020 3500.
EDIT!!!
So I ended up finally, after three days of trying everything and ordering a relearn tool off of Amazon to get the trailer TPMS to sync to the truck. What I learned was that the truck does not honk ever, I had my Girlfriend sit in the truck to alert me. I Removed the trailer profile, and added it again. Took the trailer around the block and then started the TPMS learn again. I used the Relearn tool that I got on Amazon for 9.99. I Held the little Black antenna thing right on the sidewall where it met the rim, next to the valve stem. Took about 15 seconds to learn each tire. I could not get it to work by letting air out or putting air in. I hope this helps some people, I was at my wits end Trying to figure this out.