Toyota ECHO spontaneously locks doors

Ever since I bought my 2005 Toyota ECHO the doors (all four) would lock without me touching the automatic keychain device. Neither my local mechanic for the Toyota dealer can diagnose or duplicate the problem. Today, while working about 1/2 mile from the house, the car was parked by the side of the road with the engine off. I was doing some work on a roadsign. I heard the door locks click and, sure enough, all the doors were locked. I had the presence of mind to take my keys with me when I left the car. Otherwise I would have been locked out. On a regular basis I will go into the garage in the morning and find all the doors locked. It is even possible that if I get gas and leave my keys in the car I could be locked out. Can anyone suggest the source of the problem or, better yet, how to fix it?

First off, you shouldn’t be leaving your car unattended with the doors unlocked.
That invites theft, and then you won’t have a car.

Second, if it has a remote key fob, you might be pressing the button without knowing it when the keys are in your pocket. I do this all the time with the panic button for my Nissan Altima.

If you want to prevent it from happening, pull the power locks fuse, and just unlock and lock them manually.

BC.

make a plain spare key and duct tape it behind your license plate…you will never be locked out as long as you keep the screws greased. My 07 RAV does this on occasion and I think it is an accidental touch of fob.

Thanks for your rapid response. Perhaps I should have explained a bit more. I NEVER leave my car unlocked and unattended. It is left unlocked in my closed garage overnight and, in this most recent case, I was about 20 feet from the car when it decided to lock itself. In both of these situations I was not holding or touching the Remote.

Your suggestion about pulling the fuse is extreme but, if I can’t get a fix otherwise, sure would “solve” the problem. Albeit with a bit of a hassle since I’d have to make sure all four door locks were secured - something that the electric locking does automatically.

Yup! That would resolve the problem. I may do that anyhow,; even though it doesn’t really fix the problem. Today it was weird. I was nowhere near the Remote and working with other tools when I heard the “click” from the car. I stopped what I was doing and when to the car. Sure enough - all the doors were locked. Well, at least I don’t have the Toyota sudden acceleration problem! (;op

Thank you for a sure-fire resolution.

I wonder if this a programmed event in the car’s computer that you just never really noticed as such until now ?
Any mention of the feature in the owner’s manual ?
Time ?
Distance of remotes away from car ?
A feature that can be user selected to turn off or on ?

No, no mention of anything like that. Plus, I would think the Dealer would have mentioned that. They didn’t have a clue except to say that maybe it was an airplane flying overhead. Huh???

No details in the Manual about anything special with the Remote. There are only three buttons: LOCK, UNLOCK and, on the back of the unit PANIC.

I’d love to see Tom and Ray’s take on this.

Next guess, Sticky / gummy buttons ? moisture inside ?
I’ve cleaned many many remote units here at my Ford dealer. Other than a dead battery, the next most common malfunction of the remote has to do with the five years of foreign matter build up, outside…and inside.

Some perfectly clean-on-the-outside remotes I’ve disassembled have an amount of moisture trapped inside, between the buttons and the circuit board. ( almost watery but would not just drip away like water )

Try taking yours apart as if to replace the battery. Then go a step further and remove the circuit board from the rubber buttoned face and see if a good cleaning will change anything.

The other sticky / gummy buttons could be in the car door too.

I have a chevrolet, and have gotten locked out for no reason While idleing and checking the trailer connections, I must have hit the lock button by accident I think, but then there is the rear tailgate, I never know when or why it decides to lock itself. The spare key or rolling down the window before I exit are my best options, Hey if you really are Warren, can you spot a tax deductible donation to my very talented artistic daughter at Cornish College of the Arts? She is excelling but another year there is going to be improbable at current cash reserves vs 36k tuition with room and board. I may be able to get her to create something special for you. She was a people to people ambassador to Australia by teacher recommendation, has won county fair firs and second in PTA art scholarship. She recently took a drive by offer from a guy opening an Ethiopian Restaurant for $15, and the guy liked it so much he gave her $40. Please help I am down to one piece of bologna on my sandwich for lunch, Though there are alot of people with less. Sure I think it is possible, probable, not but you never know until you ask.

I suspect the trouble you are having may be with one of the door lock switches on the doors rather than the remote key fob. The switch may have dirty contacts inside it. See if any of the switches have a touchy action to them, particularly the driver side since it is used the most.