Have a 2020 Challenger. Push button start . Ran the key fob through the wash. Dried it out (6 months ago now) and changed the battery , now if I lock the car , then next time I’m within 10-20’ of the car with the fob the right tail light flashes and the driver door unlocks. Sometimes it will do it when I’m walking away after locking it . So I figured ok I screwed up and the fob is somehow permanently damaged.

Here’s where it gets strange .

I also have a 2014 Ram . Key fob goes in the dash to start it . Out of the blue it starts doing the same thing as the Challenger.
Changed the battery , still does it .

Should mention I’m not pushing any buttons. Just happens on its own.

Any ideas?

My 2012 Challenger key fob acts up once in a while also. Mine pops my trunk as I slide my hand under the door handle as the car unlocks. I close the trunk and it will pop right open again. I smack the fob a few times and it may go away for a day or more or sometimes weeks, but comes back eventually. I think at times the fob get compressed in my pockets which is somehow keeping the trunk button pushed slightly.

So take it apart as if changing battery and look at the rubber assembly with the push buttons. There are thin concave disk that are glued in place under each button. They activate the circuits on the pcb when button pressed down. I have a 2012, that the glue broke free and the disk slide into different spot causing erratic operation of the fob. Including popping trunk and killing battery, even multi cycling as if trying remote start when key fob in range. You need a good 3M rubber cement to glue them back in place. Fixed my fob.