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Cell Phones Disable Keys for High-End Cars
Geoffrey.landis writes "Turns out if you have a top-end Nissan car, your cellphone may erase your car key. '"We discovered that if the I-Key touches a cellphone, outgoing or incoming calls have the potential to alter the electronic code inside the I-Key," Nissan spokesman Kyle Bazemore said. "The car won't start and the I-Key cannot be reprogrammed."'"
How about a website without a required login?
Nissan warns U.S. cellphones can disable car keys
Sounds like a great way to lose friends, if you take a fuse you can put it back in and everything's fine, if you fry a key it'll can cost you a ridiculous amount (near $100) to get a replacement.
:(
Then again, letting them drive runk is a pretty good way to lose friends as well
This probably only occurs with GSM cell phones. These phones use a TDMA (Time Domain Multiple Access) technique, which causes them to transmit at very high powers (2W) for short (1ms) times. Depending on the efficiency of the transmitters it's common for voltages over 20Vp-p (peak-to-peak) to be generated and transmitted to other devices.
The capacitive coupling of an antenna to a key could then be quite good at the 1-2GHz frequencies (0.5pF @ 2GHz => 150Ohms). That's a low enough impedance to power up a device (through its protection diodes) and cause it to reprogram itself due to noise on the inputs. It could actually even fry the poor little silicon device, if it rectified the voltage got up high enough (>5V) for any length of time.
It's not that hard a problem to prevent (put a filter on your inputs folks!), but I doubt the automotive key entry designers are normally thinking of transmitters at that power and frequency.
Electronic controls do not give anything that a well engineered engine does not
Huh?
Show me a car engine that can meet current emissions requirements without electronic controls while running on fuel that you can buy at your local gas station. You can't, because it simply isn't possible. Even diesels have computer controls these days.
Electronic controls are an absolute requirement for gasoline engines because of the fine level of control of air/fuel mixture and ignition timing required to burn the fuel efficiently and somewhat cleanly whilst not destroying the engine in the process.
One car I owned recently (a 1995 Chevy) had an 11:1 compression ratio and ran on 87 octane fuel (that's the lowest grade of gasoline available in most of the USA). Without electronic controls such as knock sensing, O2 sensor feedback, mass airflow measurement, and the precise control of both the quantity and timing of fuel injection and the timing of the ignition by a computer, it simply would have been impossible to reach the power level that engine developed (or even to drive at all with an 11:1 CR on 87 octane fuel without knocking holes in the pistons) and at the same time producing HC and CO emissions that were a fraction of the same size (5.7L V8) engine from ten model years earlier.
An easy example of how electronic controls have improved the reliability of modern cars is the elimination of the ignition distributor. Pretty much all modern cars do not have distributors now, because they were such a common point of failure for ignition systems that they made cars break down due to things like worn out cap and rotor, or burned points (going back to before 1975 when electronic ignition became pretty much mandatory). Take a look at the tune-up intervals in a modern car's maintenance schedule. It used to be you'd have to change half the ignition system out every couple of years - now the whole thing is good for at least 100K miles in most cases.
Without modern electronic engine controls, US cities would still be blanketed photochemical smog from vehicle exhaust, and people's cars would be significantly less fuel efficient and far less reliable.
Your statement that electronic controls are not a vast improvement over the previous mechanical and vacuum controls is patently incorrect.
Putting moderation advice in your
So Honda's logic was that the microwave is not in fact compling with FCC interference regulations, like the sticker on the back says it does?
That's not unreasonable. We usually buy the cheapest appliances, and there's virtually no testing on imports after the demo model. Since around 1995, I've seen some amazing crap inside electrical items that were supposedly UL and CSA certified.
And really, do you want to stand beside a microwave that can trigger car alarms? Take Honda's advice on that one.
These are not your regular key with an immobilizer chip. These are "proximity" keys. You just leave them in your pocket, purse or whatever. When you turn the ignition key, the car searches around "wirelessly" for the key. Same thing for opening the doors; you push a little black button on the door handle, and if you are in possession of the key, it unlocks. The car is surprisingly careful about where you have to be in order to accomplish these things. For example, it won't let you lock your keys in the car. I think it also detects the difference between a key in the driver's pocket vs. a key in the passenger's pocket and sets the driver's seat etc. appropriately.
Just bought a 2007 Infiniti G35S and it's a beautiful car.
8 8
Infiniti has been dealing with the problem quite well.
This is really not as big of an issue as the press is making it out to be -- it's a very isolated issue. I keep my phone next to my Blackberry all day and haven't had any problems. On the G35 forums, maybe 3-4 people have run into the issue. All owners recieved a letter about 2 weeks ago informing us of the issue and that they would have a replacement key for us within a few months.
Read more about it here: http://g35driver.com/forums/showthread.php?t=1537
When dealing with old-fashioned EPROMs, all bits are "1" when the ROM is erased. When you program it, some of the "1" bits go to "0" in order to represent the data you wanted to write.
Now, it's certainly possible to change additional "1" bits into "0"s into the ROM and change the data further, but it is not possible to change a "0" into a "1" without erasing the entire EPROM (by removing it from whatever device it was in and shining ultraviolet light into window on the top of the chip).
My guess is that something similar is happening here.
* Q
P.S. If you don't get this note, let me know and I'll write you another.
The Model T had two different clutches, one for going forward and the other for reverse. When the forward clutch wore down and started slipping under heavy loads, one turned the car around to go up a steep hill. Or, if the brakes didn't work, you could use the reverse pedal to stop the car.
Perhaps one could say that Model Ts were so widely used because they were more reliable than horses. It's more probable that a horse would become sick and die than a Model T engine would need replacement.
I called my sister after reading this (she has a new Altima), and she said Nissan sent out letters awhile back about the problem. They said they are developing new ones that aren't affected by phones, and will be sending out replacements.
"Oh, say, can you see by the dawnzer lee light," sang Miss Binney
Microwave ovens emit on the largely unregulated 2.4GHz band, the fact that crap on that frequency could hork up the Honda car alarm is almost certainly Honda's fault, regardless of if the oven exceeds signal strength limits or not. Especially on a security system, otherwise they've left the car owner a big wide denial of service vulnerability.
When information is power, privacy is freedom.
Check your line-in. If you have nothing connected there, disable the input at the control panel.
my clock radio
Clock radios are usually "el-cheapo" units with very high sensitivity antenna inputs. Designed for RFI.
my friend's speakers
Check the input connectors. Replace old cables, use only good-quality (gold plated connectors) cables at the inputs.
my TV
Same as clock radios.
and my computer monitor
Sorry, I can't explain that one...
Oh, and a plane's directional sensor that the Mythbusters team sat next to a phone.
I'm an electronics engineer and have worked most of my life in aerospace equipment. Electronic equipment in airplanes are *very* sensitive, they are designed to work far away from everything. There's no sense in a directional sensor that only works inside the airport. That's why no one is allowed to use cell phones in an airplane.
Cell phones (at least some GSM phones) cause short bursts of *massive* amounts of EM interference
Define "*massive*". Would a trillion (or, in British units, a million million) times do? Well, it's pretty normal for inputs in electronic equipment such as radios and TV receivers to have -120 dBm sensitivity. That means one trillionth of one milliwatt. A phone with a 100mW signal has a hundred trillion times more power than the smallest threshold a radio or TV can detect.
Cell phones are designed to have enough power to send signals through one or two concrete walls and that's all. If they were more powerful than that, their batteries wouldn't last. OTOH, radio and TV receivers are designed to detect the most feeble signals possible. The combination of a so-so transmitter in a cell phone with a non-limited sensitivity on a TV or radio is what makes RFI happen.