Dumbfounding (electrical?) Issue with Yaris door locks

[lightdisc2]

Something very strange happened today that is puzzling me. 2008 Yaris liftback 3 door. Whatever version unlocks the doors automatically when they’re opened and key is in the ignition - I have that one (power package?). My doors have ALWAYS unlocked automatically when the key is in the ignition, obviously so that a driver doesn’t lock themself out.

Today I parked my car with it still running to drop something off. I came back to my car and the car was running with all 3 doors locked. Absolutely impossible! I ended up having to wait almost 3 hrs for my car insurance to provide a lock out service. I just don’t understand how the car can possibly end up like that. All doors were fully closed and confirmed locked by looking inside the windows.

I should note I also noticed over the past few days there is a slight rattle at 3k RPM for a split second coming from under the driver side dash. I wrote it off as the cold as temps are dropping where I live. Could this be some electrical anomaly, or bad alternator? Anyone have a clue? Thanks.

[NYC-SE]

I am unaware of any Yaris trim level that behaves the way you describe. To my knowledge it is possible to lock yourself out in the same way you did. (Ask me how I know.) Is it possible that there is an aftermarket alarm / remote door lock-unlock / start system installed and that is what is causing the problem. Are you the original owner?

[lightdisc2]

I am unaware of any Yaris trim level that behaves the way you describe. To my knowledge it is possible to lock yourself out in the same way you did. (Ask me how I know.) Is it possible that there is an aftermarket alarm / remote door lock-unlock / start system installed and that is what is causing the problem. Are you the original owner?

It has never happened before, I have had the car for 4 1/2 years. I am not the original owner. I absolutely cannot reproduce what happened again, I have tried everything. When opened the doors always unlock automatically with the key in the ignition. I even tried starting the car with the doors open and locked, the computer unlocks the doors still.

It doesn't even have the remote on the key - just the old fashioned key you have to insert into the door keyhole to unlock it. I am 99% sure there is no aftermarket alarm or anything like that. This is confounding.

[sh0rtlife]

so our yairs(07 5dr canadian) doesnt do this..HOWEVER..one day getting out to lock the gate it suddenly locked the doors after they shut..window was dowm so non issue...but its never done it before or since..so ive got no clue as to the how/why....this car has never had an alarm or any keyless entry or anything like that, ..this is the typye of thing i have had to dissable on fords and such as its common on them

[lightdisc2]

so our yairs(07 5dr canadian) doesnt do this..HOWEVER..one day getting out to lock the gate it suddenly locked the doors after they shut..window was dowm so non issue...but its never done it before or since..so ive got no clue as to the how/why....this car has never had an alarm or any keyless entry or anything like that, ..this is the typye of thing i have had to dissable on fords and such as its common on them

yea very weird. thanks for the reply, it does give me some reassurance that it has happened to someone else. maybe a rare voltage issue or something, I have no idea.

[sh0rtlife]

yea very weird. thanks for the reply, it does give me some reassurance that it has happened to someone else. maybe a rare voltage issue or something, I have no idea.

yeah i was weirded out by it and did my best to replicate it , and never could..the only thing i can assume is that something happened mid warmup after moving the car 100ft which is when the vvt usually started to settle in as i always have a weird idle change right around that moment, and he timing must have been perfect for something to electrically glitch

i have had it do it 1 other time with a failing battery

[thetut]

I have seen this happen in cold temperatures where the master door lock switch is triggered by the vibrations of closing the door. It is usually very intermittent and is the reason that I always carry a spare key in my wallet. If i have the car running and will be close by I always leave the driver's window down before exiting.

[sh0rtlife]

cold weather..now taht makes sense..as the times mine did it..it was very cold..not snow on the ground or anything but cold enough to have the snow tires on it....i never connected the temperature and lock being an issue

are the 07s a transponder key or just a plain jane key?....a spare on my person would be a good idea

[thetut]

There is no transponder involved. My spare is just a regular metal key and I just went out to confirm that it not only unlocks the car but starts it.

[IndestructibleYaris]

I'm picturing some kid running up to your car, locking all the doors, and running away lol