Car unlock via phone

Locked your keys in your car ???? Did you know this??

If you lock your keys in the car and the spare keys are at home,
call someone on your (or someone else's) cell phone.

Hold your cell phone about a foot from your car door and have the
other person at your home press the unlock button of your key fob
(clicker), holding it near the phone on their end. Your car doors
will unlock. Saves someone from having to drive your keys to you.

Distance is no object you could be hundreds of miles away, and if
you can reach someone who has the other "remote" for your car,
you can unlock the doors (or the trunk!).

I just was emailed this today. If you know me, or have ever emailed me anything of questionable factualness, you know that I'm a BIG skeptic about anything I get in email being true. So, since my good friend has a brand new Buick Lucerne with a key fob, and she was the one that sent it to me, I just had to test it out. I walked out to her car and called her on her land line from my cel. We tested in a variety of ways: I held the cel phone near the car, I held it to my ear as you normally would while talking, and I put it on speaker phone. MUCH TO MY SURPRISE the car was able to be locked and unlocked repeatedly no matter how I had my phone positioned.

I am really pleasantly surprised that it works, but I guess I shouldn't be. This article mentions that the car "...monitors a radio frequency and unlocks the doors when it receives the correct digital code from the radio transmitter in your key fob..." and that kind of explains it. The cel phone transmits any kind of signal that it gets apparently, whether sound waves or RF.

I think the root of my surprise is that I didn't really think about the fact that the key fob is an RF transmitter. I guess I thought it was infrared or something, but that sounds silly now. Anyway, take it from me, it does work - at least on this car. Now I need to test more cars!!!

I wonder if you could build a device that could figure out the correct frequency and code to transmit to unlock the doors or a car and not have it take 6 weeks to be successful?

Further, I wonder what other benefits this has. I've heard of a system called Lo-Jack that is a transmitter that can be used to track your car if it is stolen. Well, what if the thief conference called like 5 other people and had them just sit their phones down? Are there not now 6 duplicate signals for Lo-Jack to track? That system may not use regular RF, maybe it uses satellite, I don't know, but it is something interesting to think about...

[Update: Read the comments first. Okay, I'm a fool. We tested it again. Originally, the person with the clicker was inside a building about 150 feet away, but was still in range it seems. The cell phone had nothing to do with it. She went much further away and then the car failed to unlock via phone. I didn't construct my experiment well. Oh well...I was too anxious to get a positive result, I guess. Kind of like those guys that claimed to have produced cold fusion. Hehe.

So, the final word from the two expieriemnts that I'm aware of is: it does not work.]