Here, we discuss a feature found in cars from a number of manufacturers that catches people with their pants down. Or rather with their windows down. So, this is not about a fault or a system failure or a warning light, but about something working exactly as it is supposed to, but doing so seemingly at random on its own.
If you’ve ever walked out to your car and found all the windows open, this is the subject. Keyless start vehicles made by BMW and Mini, Honda and Acura, Ford and Lincoln, Maserati, Mercedes, Toyota and Lexus and Volkswagen Group, include what is called a convenience feature, which opens all the windows for ventilation when the unlock button is pressed and held. The sunroof will be open as well and the car unlocked.
From what we’ve discovered only Mercedes and some vehicles made by the Volkswagen Group offer the option to close everything again using the lock button. The Honda we had for demonstration (below) did not.
So, what is causing the surprise window openings can be explained by accidental button presses. Whether carried in a bag or in a pocket, something pressing on the unlock button for an extended period can and will activate the feature, if the key fob is within 50 feet or so. Remember that while the fob’s keyless access can only operate within 18 to 24 inches of the vehicle’s door handle, the buttons on the key fob will work from a much greater distance.
For a fob carried in a pocket, preventing this may be a simple as turning the fob over on the key ring. The buttons will face the other way if your keys tend to rest in the pocket the same way each time.
If it is carried in a bag, the nature of keyless open and start can easily lead to the fob migrating to the bottom of the bag. Anything and everything sitting on top of the fob can and will activate the feature.
In this case, you might try using a device like a carabiner or snap hook. It can be hooked to a strap and still actually be closed into the bag. But it won’t work its way to the bottom. The devices come in many different sizes and colors so you can be a stylish as you’d like and they can be found online or at most hardware stores.
To finish the discussion of the functions of the actual convenience feature, the windows will stop short if the button is released, and will continue down if it is pressed and held again. Some vehicles require the unlock button to be pressed and released once before the convenience feature will work.
In Honda and Acura vehicles, the feature can also be activated by holding the mechanical key turned to the right in the key cylinder, but this will not happen accidently. Also, turning and holding the key back to the left will close the windows and sunroof.
The feature can be disabled in Ford, Lincoln,Toyota and Lexus vehicles, but you’ll need your dealer. In fact, the feature in a Toyota and Lexus must have first been activated in this way.
So, if ever you find your windows wide open one day, don’t panic — find a new way to carry your key fob. Below is a video we did as a visual aid.