My experience as a very exigent user tells me that system manufactures should keep it as simple as possible.
In instance, a Nissan Sentra has nothing but close and open doors command at the key fob, it has no windows remote control, so that, if the driver closes the car, and it gets open in the future, the car will simply gets itself closed again in a few minutes if no door has been opened. Simple as that.
There are automotive systems that doesn't bring easiness to the user, those shouldn't be installed.
Just a few comments:
Regarding the capacitive sensor... I hope you're not telling me (as a customer) that I have to remove my gloves in the Michigan winters in order to operate my keyfob. If you are, I will never buy one of your cars again!!
Likewise with the double button press or activate switch. I find it hard enough to press the buttons with gloves on as it is, much less to press 2 buttons at the same time or activate a slide switch etc.
I'm very confident (having worked on remote keyless systems for over 10 years) that most of the above suggestions would result in far greater complaints from customers annoyed by these "features" than the complaints of inadvertent activation.
My gut feel is that some fobs are poorly designed and are more prone to inadvertent activation than others. The clearance from the carbon pad to the circuit traces, the stiffness of the rubber, the profile of the surrounding plastic all contribnute. I suspect that good design of the mechanics of the fob would go a long way toward preventing this problem. (john_#3's comments support this.)
As far as remote start overheating goes, all of the remote start systems I have been involved with have a timeout in the range of 5-10 minutes thus making it very unlikely that the vehicle would overheat (or burn excessive amounts of fossil fuels.)
As far as someone "listening in" on the RF signals from the fob to the vehicle, all "modern" (10-15 yrs old or less) remote keyless entry systems use a rolling code system which makes it virtually impossible for a thief to replay your signal and unlock your car. There is a theoretical "crack" of the Microchip Keeloq system, but practical useage would be very difficult. The "stories" of thieves replaying an RF message come from very old systems with poor security (much like the old garage door openers that used a simple RF frequency or a "fixed code" system.)
How about making remote start illegal? At least in my part of Michigan it is a large source of air pollution, as a car sitting warming up is getting ZERO miles per gallon = 100% pollution. Next, how about the option of no power steering or power brakes? I know that power brakes are required to enable traction control and ABS, and undoubtedly they will be needed for the stability control fiasco that will be soon required for everybody. Haven't the safety people discovered that many of us drive much better than a 16-year-old? The other problem with the current design of remote fobs is that accidental pocket keying can certainly shorten the battery life, even if it does not leave your lift-gate open to the world while you are shopping. The very least that the car makers could do for us is to add a "remote off" switch someplace in the car.
Not only can an accidental remote-start happen, but it has happened to me on a Jeep. Luckily, only a few minutes later I found the car running. The good thing is that the doors are automatically locked when a remote start is in progress.
jpmcwil, no you're not the only one who feels that way. I was able to buy my new pickup truck without power door locks or power windows. I was not able to buy it without power steering, power brakes, cruise control, or an automatic transmission. This seriously worries me. One of the first things I did during the test drive was get it up to 15 mph and turn off the ignition switch, to make sure I could still steer and brake it if one of those powered systems ran away on me and I had to shut down the engine to kill the hydraulics and regain control. Detroit needs instruction in the KISS principle, not to mention fail-safe design and graceful degradation.
I had this problem with the (rather huge) paging-remote fob for my truck.
I liked the 2-way capabilities - I never had to wonder whether I'd locked the truck, or whether that alarm I heard going off in the distance was mine; the fob knew. But it was subject to accidental button press. After one too many, I opened it up and shaved most of the fronts off of the silicone buttons, recessing them. I never had another accidental activation, and they were still easy enough to press intentionally.
The key fob on my Grand Caravan also includes the anti-theft key identifier, so I must use that key, and not a simple plain copy. The very worst thing that they did, A REALLY STUPID choice, is that there is no key option for the passenger side doors. Only the drivers door has a key to open it. There is the very poor option of opening the rear gate and climbing up to the front, but that is a pain. Worse yet, to unlock the passenger side door with the remote, the only option available is to unlock everything, which allows a street punk to quickly open a door on the opposite side and steal a laptop computer. HOW STUPID CAN A CHIEF ENGINEER GET! Save a bit on a car and assure that people will never purchase another vehicle without a passenger side key lock installed. Those who made that cost-cutting decision are not nearly smart enough to get the monkey badge.
What does work very well is the "putting the keyring in my pocket door unlock" function. How about requiring pressure on two buttons with a ridge between them in oder to activate a function? Fairly cheap, and quite easy. The "enable" button could be in series with the battery connection, not needing additional logic.
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