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My vehicle is turning itself on and off

Last night my 2007 Toyota 4Runner started up on its own. The vehicle had been completely turned off, the keys were not in the ignition, and it doesn’t even have a remote start. After a little while, the vehicle then turned itself off. It continued to turn itself on and off throughout the night. Does anyone have any idea what could be wrong with my SUV?

Umm that’s not possible UNLESS you have remote start. I belive that your car has a chip in the key, no key no start. It’s that easy. So even if you had a short in the ignition switch, that powered on the fuel and ignition system and powered up the starter (really not possible) with out the chip in the key it still would not start.

I am guessing you got this truck used?? I am also guessing the truck has remote start and that you never got the remote for it when you purchased it.

Or does this car have an alarm?? I ask because I had an impala that had an aftermarket alarm put in, but they wired it to the factory remote and I had to hit the lock and unlock buttons at the same time for 5 seconds to start the car. I found this out by accident 6 months after I got the car.

Is you car 100% OEM or has there been some modifications, even if they don’t seem to you to be related like maybe a new radio etc?

The car has become aware. May I suggest you don’t stand in front of it at any time? If is only a matter of time before it figures out how to move the transmission stick. Questioning its own existence is likely right after that…

Seriously, a previous owner may have installed a remote starter feature and it must be malfunctioning. Does it have an alarm? If so, is it possible that the remote button on on of the buttons controls your remote start feature? Maybe the feature failed a while ago because the button died so it was sold as not having a remote start feature. Maybe that button has some sort of intermittent issue.
To test that theory, take the batteries out of the remote or pug the remote in a tin (ie metal) cookie box over night to see if the problem goes away.

did you buy this truck new or used?

I’m with those that believe this is a remote start related issue. When I lived on the frigid winter plains of Saskatchewan I had a remote start that would respond just as described by the OP when the temperature fell below a certain level. The only time I ever used it was when I was parked somewhere with no plug in for my block heater. The other potentially deadly problem associated with this program feature was having your car/truck start up in the middle of the night in your attached garage. Not good. Me, I just had a timer connected to my block heater to go off about an hour before I had to go to work. Got to remember to unplug before backing out of the garage though!

It’s either a remote start issue or your teenage son and his girlfriend were in there and kept getting cold.

I work in a company’s garage. Today we had a 2002 Ford Expedition where there was 0.15A current flowing on the ignition wire running from the ignition switch to the solenoid with Key Off. Disconnecting the wire we had over 4 volts at its end (at the starter relay switch). - should be zero! Maybe 10v and it would start by itself. a lot of our trucks here where I work, are Fords, we’ve had trouble with the multifunction switch, ignition switch, and light switch, in high mileage commercial use it’s fair to say. Something malfunctions inside. But it’s usually an open circuit.

I looked up the circuit for your starting system. And the only way the engine can start on it’s own and run is if the Engine Contol Module is commanding the starter relay to close it’s contacts causing the engine to start and run.

Following any other path thru the circuit would prevent the starter from operating because of the ignition switch and the park/neutral safety switch.

So it’s got to be a problem with the ECM.

Tester

We had another one of our Econolines - and again, after many years of heavy service - where it kept cranking until it fried the starter…like when a person turned the key, and then released it like you normally do…turned out to be the ignition switch. Didn’t “release” or something. but it was the switch itself. had springs or something in there. this isn’t a “crank by itself” but another example of ignition switch gone bad. I’ve also seen cars where high resistance in ign sw affected many of other systems, like when you turn it to Acc it supplies a lot of things - as in Run. Ign sw gets heavy hammering over & over by impatient humans!

Is it possible it isn’t actually running, but merely that the starter motor is cranking? Has the starter motor been acting up? Clicking instead of cranking? Sometimes the starter selenoid contacts can sort of weld together, and temperature changes could cause the starter motor to engage for while, then shut off. If so, be caution is in order, as this could cause an engine fire. I’d disconnect the battery until this gets fixed.