Unlocking your car door with… A tennis ball

For some reason, it seems to be unavoidable: there inevitably comes a time when we find ourselves on one side of our locked car door, with the keys on the other.

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National Bank Insurance
Published on 2014/08/05

If we’re smart, we’ve got a backup set, but what do you do when the extra keys are with your significant other, and they’re out at a tennis match?

A sporty solution

Let’s imagine that I’m the sporty type, and that calling a locksmith or roadside assistance is an insult to my athletic sensibilities – only a solution that uses my muscles will do. Then what? I break the window? I pick up the car and shake it, in the hopes that the keys fall out? I pull a Hercules and peel back the roof in a single go?

I don’t think so.

I just grab my super-sporty emergency kit and pull out a tennis ball. I’ve seen this done online, so it must work. I pierce a hole in the ball, press it against the lock, give it a good squeeze, and there you have it!

The principle

You can see for yourself, there’s another video demonstration here (try to disregard the production quality and somewhat dubious commentary). Now, take a moment to think. What are you really looking at? A ball is squeezed, a door opens, but is one related to the other? Is it possible that someone is using the remote key off-camera at the same time?

The idea behind this “trick” is that when the air in the ball is compressed, it exerts enough pressure on the lock mechanism to open it. Some people will say that you need to put a seal on the lock, or that you need to burn the edges of the hole for it to work. We could even take it a step further, and say that it only works on pump-activated central locking systems (which already work based on air pressure, and are mainly found in European cars) or on old models (ideally with bad paint jobs). 

Myth or reality?

I have a confession to make: I’ve only tested this on one car. My one and only attempt was a giant fail, and I didn’t relish the idea of having to explain to a police officer why I needed to play with the locks of all the cars parked on my street. However, the television show Mythbusters tried it, too, and came to the conclusion that it’s impossible (even using ten times the pressure of a tennis ball).

Personally, I’m less categorical. It does seem unlikely with newer vehicles (a colleague, reading over my shoulder, just told me that his car doesn’t even have a lock on the door…), or with electronic key systems… But it is possible that this is something that worked on some cars, at some point in time. 

In short, I wouldn’t worry too much about it. Even though tennis is on all our minds this season, a tennis ball is not going to help anyone steal your car. Unfortunately that also means that you won’t be able to unlock your own car this way either, if you’ve locked your keys inside. In spite of everything, if you’re still worried about theft, there are some easy prevention tricks, and lots of anti-theft devices that could even get you a discount on your car insurance.

All right. Now it’s time for me and my muscles to go shake my car and see what comes out.  

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