Locked out of your car? Phone a friend. Urban myth resurrects

An urban legend re-emerges. Unlock your car by getting a friend/partner to push the spare key’s button over a mobile connection.

Although this trick has been de-bunked by many eminent engineers as impossible, even their criticisms are flawed. Most denials centre on the radio frequency at which car remote locks work.

This is reputedly between 300 and 500MHz, whereas mobile phones start at 450MHz and go up to 2.1GHz. But this is irrelevant because some car locks use sound waves rather than infra-red.

So, it would seem possible for this to work with older/cheaper cars. Plus people tend to be very insular in their approach to what a mobile phone is designed to do.

Hence they point out that handsets are designed ‘only’ to carry the human voice. Yeah, but that includes Xhosa and that seems to work fine in South Africa.

Anyway, the solution is to try it for yourself. Get your accomplice to put the spare keys next to the mobile’s mike. Hold your own handset about a foot away from the car. Press the button.

A whole bunch of people say it works here. While a list of disbelievers and de-bunkers can be found here.