[Dunrollin]

Yes, you are not alone, I have had false alerts, but with the horn and signals. Now what? It either never happens again or becomes a constant annoyance. I looked over at f150forum.com and it seems there are several others with this issue. They seem to point to the BCM and water as the problem and suggest pulling all codes with forscan. Here is the thread (well, one of the threads) Hazards and horn operating erratically . Now his is older (a 2016) but the basics haven't changed. His summary is

UPDATE: It was the BCM that was damaged due to water intrusion due to an incorrectly installed windshield. I ended up taking it to the dealer to have them deal with it, because this late in the game, as a single daddy with an 80-mile round-trip to work every day, I needed my truck to be solid and reliable.

Where I originally was looking at the door harness seals for water leaks, it turned out those connections were good. I'd have never expected my windshield to have been the cause. You get those installed and figure the guy knows what he's doing.

The work order came out to just over $1000. A guy was to come and reseal the windshield, and all was supposed to be well. Then I got a call saying the windshield was going to break upon removal (most likely), and I'd need a new one installed. Work order just jumped up to $1300. After some "discussions" the dealer was able to knock a few hundred off the labor, bringing me back around $1000 to fix everything, All in all, I missed two days of work due to the truck being down, which probably brings the loss right back up to $1500, but such is life. I'm just hoping we are good to go from here. I'm usually really good with preventative maintenance and making sure problems don't get super expensive, but I didn't even see this one coming!

Another issue that causes these symptoms is a low battery.

Mine went off at 2 AM and in a locked garage. I ran the security camera and at the same time it went off a fire truck went by. Who knows? Also I think some or all trucks have a trailers security system built in that Ford kind of screwed up- it is supposed to let you know when someone unplugs your trailer without your key fob nearby. It can be disabled if you see it is on your truck.

 

[Dunrollin]

Certainly an aggrevation. Did you try using electric tape squares over the inside sensors in the overhead console? Mine goes off about 1 time each week but it is because I lock it and forget my dogs are inside while shopping and about the time I get into a store off it goes. As you mentioned I just silence it with the app and leave the truck unlocked until I get back out. You would think I would learn...