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Locked out ? Maybe not

  1. Jan 13, 2010 #1

    rhody

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    Locked out ??? Maybe not...

    With the cold weather coming on and a recent incident at work with someone locked out of their car running with keys left in the ignition.

    A possible solution (car must have automatic door locks), I tried it and it works on my Honda.

    Both parties must have a cell phone.

    The party with the spare key and opener calls the stuck party, who in turn puts their cell phone next to the locked door, presses the button, and bang, it opens the door, I tried it and it worked for me.

    Also anyone with OnStar, etc... that is part of the service you pay for, they can unlock at will with a password as well.

    On an older car I had an autostart, and at times it would lock me out with the key in the ignition and the car running all by itself. I learned to carry a spare valet key that opened the doors and used it a few times before my daughter totaled the car.

    Maybe some IEEE folks could tell us why some locking systems work and some don't using the cell phone trick.

    Hope this helps if you are stuck.

    Rhody...
     
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  3. Jan 13, 2010 #2

    BobG

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    Re: Locked out ??? Maybe not...

    It doesn't work with any remote keyless entry system that uses RF (probably over 99%). It will work for systems that use sound (I've never personally seen a system like this).

    Testing to see if this works on your own car is a two-step process. Do the cell phone thing. Then try it again without the cell phone. In other words, if you're calling from inside your house to unlock your car sitting in the driveway, the reason it works is that the remote is still within range of the car.

    My dad used to keep a spare key in a little tin box affixed to the underside of the car by a magnet. Listening to his end of the phone conversation when my mom locked her keys inside the vehicle in the days before cell phones was priceless (having to call on a payphone, try out his steps, and then call back just added to the experience).

    "What do you mean the key isn't there?"

    "The only thing you found was a crusty magnet with a rusted piece of tin glued to it?"
     
  4. Jan 13, 2010 #3

    rhody

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    Re: Locked out ??? Maybe not...

    BobG,

    I am pretty sure that the cell phone to cell phone distance was over the distance that the key would nornally open the lock without it. I don't know if Honda uses RF or not, my car is an 07 model. I was surprised as well.

    I will try it again at an even greater distance, say 1/4 mile and report back. As an aside, I notice when I leave my cell (turned on) on top of an electric alarm clock and before it rings, the alarm clock buzzes before the cell rings everytime so obviously there is some kind of electronic coupling with the radio or alarm clock with the incoming call.

    Rhody...
     
  5. Jan 13, 2010 #4

    Mech_Engineer

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    Re: Locked out ??? Maybe not...

    On my Toyota 4runner it's basically impossible to lock yourself out. If the key is in the ignition (running or not) you cannot lock the door if the door is open. If you press the electronic lock button, the doors immediately unlock; if you physically press down the lock on the door, it automatically pops back up. I've even tried using a second key fob to lock the doors from the outside with the car running, doesn't work.

    The only way to lock the doors on the car while it is running is with the doors closed and pressing the door lock button (or physically pressing down the lock on the door).
     
  6. Jan 13, 2010 #5

    BobG

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    Re: Locked out ??? Maybe not...

    Range varies by manufacturer and by region. For the US, maximum range is around 60 feet, but most manufacturers have a smaller range. Honda probably has a range around 30 feet (even though maximum range in Japan is about 15 feet). I don't know how these are tested, but it's a trade-off between maximizing how far away a vehicle owner can open their vehicle and FCC regulation of RF traffic (obviously, the RF signal goes on for infinity, but has to be below a certain power level within 60 feet - a much more sensitive receiver could extend the range beyond 60 feet without violating FCC regulations).

    None the less, the only way to know for sure is try opening the vehicle with the cell phone and without the cell phone. That way you don't have to mess around with figuring out the range of your RKE under various conditions, etc.

    Apparently, extending the range of RKEs is pretty important to some people:

    How come I never see any of these people in the parking log? I guess I should be glad I own a Jeep. I don't have an RKE.
     
  7. Jan 13, 2010 #6
    Re: Locked out ??? Maybe not...

    What about remote starters? I am guessing they have different RF regulations because they can go up to 200 feet or so.

    My car is impossible to lock the keys in, because there is no wireless entry, and whenever you shut a door the lock pops open!
     
  8. Jan 13, 2010 #7

    BobG

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    Re: Locked out ??? Maybe not...


    Is yours a newer car? With advanced remote keyless entries, the fob merely has to be within a proximity bubble to unlock the doors. The doors refusing to stay locked when the fob is in the car is typical for those systems.

    Actually, this system isn't so new, since the first was installed on a '93 Corvette. Maybe that's what's really happening with Rhody's system? (One variation of the system has the doors unlock when owner touches a sensor, usually behind the door handles, whenever the fob is within the proximity bubble).

    Remote starters work in a different frequency range than remote keyless entry (and different than cell phones if anyone thinks it's the cell phone signal activating the RKE). AM remote starters have ranges similar to RKEs, while FM remote starters can have ranges up to a mile under perfect conditions (the FM starter is particularly useful if you're in a profession where people routinely call you "Godfather").
     
  9. Jan 13, 2010 #8
    Re: Locked out ??? Maybe not...

    Nooo my car was made during the pinnacle of Nissan engineering. . . . . .



    1987.
     
  10. Jan 14, 2010 #9

    rhody

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    Re: Locked out ??? Maybe not...

    I tried it again, this time at a distance of at least 1000 feet in one case, and over 30 miles in another from the sending cell phone, using two different phones, (different brands) different phone services and sad to say, it may have been one of those cases where if was actually picking up the unlock signal from the key and not the cell signal (because the first time I tested it was local and probably less than 500 feet away.

    As far as I am concerned case closed it doesn't work as I originally thought. It would have been nice though, because I don't have OnStar in either of our vehicles.
     
  11. Jan 14, 2010 #10

    FredGarvin

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