Shadeux said:
My Google-fu came up with:
1. A lot of people report this happening.
2. Everyone makes jokes.
3. There is no consensus about how this could happen.
I expect 90% are "I didn't know I had remote start," or perhaps a prank using another key fob, but there is 10% left with "I donno?" FCA products seemed to be the majority that exhibit this. My pet theory is automobiles with remote starting in the software but not equipped with the hardware are starting on their on. Perhaps key fob vs. not equipped with remote starting but still things can get mixed up with 80 billion lines of code in the software? Just my two cents.
There is no special hardware, though. It's all software.
Granted, your point is still valid. Weird things happen.
I don't have any advice aside from a battery disconnect switch. my dad had a 91 or 92 Pontiac Bonneville SSE , that he bought new, that did all of these tricks. He parked in a ramp next to the toll booth. He would get a phone call telling him that his windows are going up and down or that it was starting on it's own. If i recall he took it to the dealership 30+ times in 16 months.
Good luck finding the issue
I came here to say I can probably start my Saturn with a screwdriver because of how screwed up the ignition lock cylinder is but that's probably not what's going on here.
NickD said:
Did she buy it new or used? If she bought it used, did a previous owner have an aftermarket remote start installed and removed at a later point? We had a Lumina-based Monte Carlo that someone had had a remote start hacked into and then removed before they sold it. That car was prone to starting itself randomly and it would run until you either noticed it or it ran out of fuel.
If she bought it used, an aftermarket remote start that was poorly installed or poorly removed would be my guess.
I have had this happen on the family truckster while we were 400 miles from home. One of the previous owners had attempted to install a remote start system in our 2004 Explorer. We were visiting the wife's parents and when we went to leave to drive home, all the windows rolled down, the instrumentation died and none of the exterior or interior lights would work. I had to be at work the next day so we drove it to the nearest Ford dealership. They agreed to diagnose it. After waiting 5 hours in the dealership with a 1 year old, a 3 year old and incredibly pissed off wife, the techs found a bare wire that was spliced into the dome light to provide power to the half installed remote start system. It was shorting out inside the driver's side a-pillar. They also found a half dozen poorly spliced wires. They repaired all of the hack job and we finally were able to drive home. We had owned the truck for about 4 months at that point. That was berkeleying horrible 
.
Prior owner of a 2011 Routan SE as well - We didn’t have that issue but we did have the well documented TIPM issue which would cause hard starting and the horn and lights to go loco. Even after I fixed it with a relay box jumper kit, it still did weird electrical stuff until I put it a new battery. I know the TIPM affected the fuel pump, maybe it could blip the starter as well?
Someone reached under the dash ripped loose two random wires and touched them together.......
Grizz said:
My mom called me and said her Routan was running in the driveway when she got home from going shopping. Doors locked and no key in it. All I've seen online is the opposite problem with not starting so I'm drawing a blank.
I mentioned my parents Hyundai starting on it's own as well in a earlier post. I discovered it has a cold weather mode that can be activated with the correct combination of key fob button presses. This mode will cause the car to start every 2 hours and run until warmed up. The mode remains active until 25 starts with the key occur, or until it is deactivated. Might want to see if your mom's vehicle is equiped with something similar.
