By The AsiaOne Techbot

Left your keys in the car and got yourself locked out? According to an email that has been circulating online for years, all you need to do is to call home for help.

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And no, we don't mean getting someone to drive down to where you are with the spare keys.This email, which had apparently made its rounds online for about a decade, says that mobile phones can act as emergency car keys.

To do this, the email instructs readers to simply call someone who has a spare key, and have the person put the key near the phone while pressing the 'unlock button'. Signals from the spare key will then be transmitted across the phone network to unlock the car.

An email example dated 2004 reads:

Subject: Unlock your car from the outside!

This only applies to cars that can be unlocked by remote control. Should you lock your keys in the car and the spare keys are home.

If some one has access to the spare remote have them call you on your mobile phone.

Hold your (or any) phone near your car door and have the other person press the unlock button, hold it near the phone.

Your car will unlock. I tried it and it works. Saves someone from having to drive your keys to you. Distance is no object.

You can be hundreds or even thousands of miles away.

True?

Tough luck, but if you've locked your keys in the car you'll probably need more help than that. Keyless entry works on radio frequencies, which unfortunately, can't be transmitted over a phone line.

So the next time you forget your car keys and see them sitting on the dashboard, don't count on having your phone magically opening the door for you.

There are lots of things our mobile phones can do, but in this case you'll probably still have to beg Mom or Dad to drive your spare keys to wherever you just stranded yourself.