doors lock and unlock on their own

Some possibilities:
1. buttons get pushed inadvertantly while the fob is in your pocket (this is easy to do)
2. where is the second fob when this happens? perhaps its battery is dying also, or maybe someone is screwing around with it to gaslight you.

 

<_< Some past postings made similar comments when washing the car... sounded a bit like the water was causing the smart system to lock or unlock the doors - as if water seeped into the door handle mechanism. That, however, couldn't explain the other situation.

 

Maybe the button is getting suck.
Try using the second fob and placing the current one far enough away that it won't contact the car.

 

When I wash my car and have the fob in the car or in my pants with the doors locked it will unlock and lock every time water gets behind the handel. I now just unlock all the doors when washing and don't have that problem anymore. I don't know about the second issue.

 

<div class='quotetop'>QUOTE(theforce @ Aug 2 2006, 01:47 PM) [snapback]296456[/snapback]</div>

If the fob is within distance and the sensors get triggered, it's going to do that. Kinda like going near a sink or hand dryer that has the optical sensor on it. Your best bet is to just disable smartkey until you are done washing the car, then re-enable it.

 

the fob only works within about 3 feet of the car. so if you and the fob were in the house, and the car was out on the street, the signal wouldn't reach the car.

mine also does the lock-unlock with the key in my pocket, i just leave the key in the house now.

the car will re-lock itself if you unlock it but don't open the door... could that have been the situation? anyone else nearby have sks? our neighbors have a lexus with sks and it freaked me out for weeks after they moved in.

 

<div class='quotetop'>QUOTE(xrep @ Aug 2 2006, 02:20 PM) [snapback]296430[/snapback]</div>

I had a similar experiance with my 06 while washing it.
here is what it might be.
if you have the fob in your pocket and you are washing the car you will accidently hit the rubber lock button on the outside handle.
You wil of course hear the car lock as it should.
As you continue washing the car you will probably wash under the handle and the car will take that as a signal to unlock and you will hear it unlock.
So now you move on washing another part of the car and you hear it lock again when you are not near any part of the car that would make it lock.
This is because the prius is programed to relock itself if you unlock the car but don't get in within a certain amount of time.
The washing routine has triggered this mode because you inadvertly locked and unlocked but didn't enter the car.
There is nothing wrong with the car .... it's YOU !!

Try this test, with the FOB in your pocket press the rubber button on the handle and lock the car.
now reach under the door handle but don't pull it, the car will unlock.
now just stand there and do nothing, the car will relock itself in 30 seconds because no one entered it.

The same thig happens if the car is locked and you accidently press the unlock button on the FOB.

I think this car is to smart .

 

<div class='quotetop'>QUOTE(theforce @ Aug 2 2006, 11:47 AM) [snapback]296456[/snapback]</div>

My best guess: The car doesn't know your fingerprints. It's just completing a circuit then you touch the handle. The water, being a good conductor of electricity, is doing the same thing your hand does.

 

Our 2006 Prius has begun to lock itself even when both sets of keys are lying some distance from the vehicle. Could the alarm batteries need replacing? Can the replacement batteries be purchased more cheaply someplace other than at the dealers?

 

There are no "alarm batteries". The 12V battery could be on its way out. They usually last about three years; less if you abuse them.

Any chance you have unlocked the car but not opened the door? If you do that, the Prius will relock itself.

Tom

 

Doesn't the keyless entry remote control have a battery? I'd think it would not be able to function without one.
The car was locking itself when all doors are unlocked and we walked away from it. However, since I wrote to ask about it, it has remained unlocked all day. It makes me uneasy, however. How long do the keyless entry remote batteries work, and would this erratic behavior be a symptom that a replacement may be needed? Thanks

 

I'd expect that the first symptom of dying batteries in the fobs would be difficulty in *un*locking the car or in starting it, because dying batteries reduce the fobs' range.

Unexpected locking might indicate a dying 12V battery as Tom wrote. If you have a voltmeter, leave the car OFF for an hour and check the voltage at the jumpstart terminal. You can also have the car do a self-test of the 12V battery with no tools needed. See the procedure given in jdedenberg's post in the thread here:
PriusOnline.com &bull; View topic - how to put 12V battery in sleeping mode?

If you find less than 12V the 12V battery is near the end of its life and may well be causing weird behavior.

 

The fobs use a standard coin type battery, which you can replace on your own. The normal indication of a failing fob battery is limited range. The battery in a fob is usually good for several years, but will vary depending on how the fob is used. If it is stored near the car or near an RF source such as a cell phone, battery life will be reduced.

Tom

 

Here's the explanation behind the doors locking & unlocking when you wash the car.

The handles have capacitive proximity sensors in them - you don't have to actually tough the door handle to unlock the car - try it! These sensors can be fooled when you direct a stream of water toward them, if you're close enough that the doors also sense the keyless entry fob in your pocket.

That explains the unlocking - the best solution is to put the keys somewhere more than ~3 feet way from the car while you wash it.

Another feature of the car is that if the doors are not opened within 30 seconds of their being remotely unlocked they will automatically relock. I guess the designers figured if you really meant to enter the car you'd do so within a short period of unlocking it. This helps correct any issue with the doors accidentally unlocking without the owner knowing about it.

Put these two behaviors together and the result is that the doors may lock and unlock periodically when you wash the car.

Probably the best thing to do is put the keys inside the when you wash it (if you dare). The sensors in the passenger compartment and trunk won't let you lock the keys in the car (try it!) so they will break the lock-unlock sequence.

Or just have the doors unlocked when you start washing.

 

You can also disable the SKS by pressing the little button under the steering column. Or just do what I do and let the doors lock and unlock while you wash. I find it kind of amusing.

Tom

 

The water issue is addressed on page 45 of the 2009 owners manual. In addition to car washes, it also mentions large amounts of water from rain.

 

Car washing isn't an issue with my Prius. That was in the post of another member. It's interesting information, however.