Car starting self

My parents have a 2013 kia sportage and got it almost 2 years ago. It has a dealer installed remote start as does my 08 kia spectra. Last week I parked next to them (like i have the past 4 years) and I get out of my car and their car starts itself. The lights were on and the radio inside was on. Next day it did the same thing, except during the day. It has done this every day since the snow thawed. Now we disabled remote start using info from the vehicle instruction manual. Now as I type this it is outside making subtle honks and flagging lights like I’m trying to lock the thing with my remote. I’m not sure what is going on!

Two things come to mind. Either the module that controls the door locks and remote starter is recieving an RF signal to activate, or it is malfunctioning. You could try to rest the module by clearing out the key fob memory and resyncing the key fobs. Instructions should be in the owner’s manual. Or, take it in for warranty repair. Don’t forget to take all the key fobs that are used for the car. If the module needs to be replaced, they can get the fobs resynced if they have them.

I’d say that chances are good that your spectra and their sportage use the same RF frequency - or in one way or another have frequencies that mess with each other. I do not know a lot about the technical end of these wireless systems. I do know, however, that if Kia makes a million cars, a million discrete and independent RF frequencies are not assigned. I’d say that if you want to resolve it, both cars probably need to end up at a Kia dealership at the same time. Many locksmiths these days can also handle these systems is the dealer isn’t a good or easy option for some reason.

But it never did this before. Just now. It doesn’t make sense because if that was the case this should have been happening all along

Well then, you’re obvious left with a malfunction. What is going on is that the car has to end up with a dealer who will scan the car’s system to look for faults.

RF circuitry can be sensitive to all sorts of stuff you wouldn’t normally wouldn’t think about. I don’t have cars that start by RF remote, but my automatic garage door openers which I’ve used various models for years do have RF remote control. One of them would open whenever my spouse used her sewing machine. Never did figure out what caused that. I just told her to make sure there was nothing in the way of the door before doing any sewing. Another one would work for years without a problem then all of a sudden it would work one day, and not the next. When I opened it up, there was a spider crawling around on the circuit board. The spider’s body capacitance must have been changing the tuning of the circuit. I convinced the spider this wasn’t a good home, to move on to a new place to live, and the door started working reliably again.

If I had this problem I’d ask if it is possible to disable the remote start feature.