2009 Jeep Grand Cherokee locked and sitting in the driveway yesterday - a sunny, warm day. No one around. Rural area, no near neighbors. I heard the Jeep start up - and the lights went on. The keys were on my kitchen counter. There is no remote starter on this vehicle. How could it have started by itself?
It was not easy to turn the engine off. I unlocked the vehicle. I put the key in the ignition and tried to turn it off. That did not work. I tried to turn off the lights and could not. I fiddled with all the knobs to no avail. Finally I stepped on the brakes and the engine shut down and the lights turned off. Does anyone have a clue how this could happen?
Stepping on the brake is exactly what shuts down my remote start if you have not yet put in the key and turned it to run position.
Sounds like it has a remote start system on it that you don’t have the remote for and it reacted to someone else’s signal nearby.
If this is a new occurrence look at your neighbor’s driveways for a new vehicle and ask them if it has remote start, then ask them to test start theirs to see if yours starts too.
Dont forget the neighbors you can’t directly see like behind you or even the next block over.
It might not happen every time if the neighbor’s system is a random frequency changing system.
Ken is right. Your vehicle has a remote start that you are not aware of or it’s possessed. Did you purchase this vehicle used?
Thanks Ken and Missileman, The vehicle was purchased used. I have no remote and so did not anticipate self-starting. When I mentioned the problem around the break room several people said it must have a remote receiver. So other people agree with you. It is still odd though. I have no near neighbors. The nearest is a short drive, and a stand of forest is between me and them. There is a lake that is fairly large. Maybe a signal could project across open water, but it seems too far to me. Could it be that Stephen King’s Christine has come to life for real in my driveway?? 
You shold have a remote built into your key to unlock the doors which may or may not have a remote start button. The remote start button is labeled “X 2” encircled with an arrow.
“REMOTE STARTING SYSTEM — IF EQUIPPED
This system uses the Remote Keyless Entry
(RKE) transmitter to start the engine conveniently
from outside the vehicle while still
maintaining security. The system has a range of
328 ft (100 m).”