Yesterday a law enforcement source told me that thieves were using fob signal amplifiers to get into cars, such as Volts, parked in driveways where the fob was in the house 50-100 feet away. He told me I should store the unused fob in a metallic Ziploc type bag widely referred to as a Faraday cage. GM ought to notify owners of the problem and provide them with these bags.
Fob signal amplifiers and owner protection
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It doesn't seem likely as the FOB doesn't transmit unless you push the button. I'm pretty sure the range on the volt is easily 100 feet anyway without amplification.
Now what criminals could do is setup a receiver to capture the signal when you do unlock the car and drive away. Then the next evening they can walk up the the car and unlock it. But then some higher end vehicles have a rotating code so it has a preset algorithm that changes each time to thwart the simple recording and retransmitting of the signal. It's a cat and mouse game.
Edit: Oh wait, the car does transmit something the the proximity sensor near the doors so you can press the button to unlock. So I guess it is feasible that they use such an amplifier to get the signal from the fob strong enough to unlock the doors and start the car to drive away. But as America's best kept secret, wouldn't they criminals be going after the neighbor's BMW instead? Then after they attempt to start the car, when they don't hear the starter crank and engine fire up, maybe they will leave and go after another vehicle.
Now what criminals could do is setup a receiver to capture the signal when you do unlock the car and drive away. Then the next evening they can walk up the the car and unlock it. But then some higher end vehicles have a rotating code so it has a preset algorithm that changes each time to thwart the simple recording and retransmitting of the signal. It's a cat and mouse game.
Edit: Oh wait, the car does transmit something the the proximity sensor near the doors so you can press the button to unlock. So I guess it is feasible that they use such an amplifier to get the signal from the fob strong enough to unlock the doors and start the car to drive away. But as America's best kept secret, wouldn't they criminals be going after the neighbor's BMW instead? Then after they attempt to start the car, when they don't hear the starter crank and engine fire up, maybe they will leave and go after another vehicle.
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Was the source, perhaps, wearing a foil hat to guard his brain signals?
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This was discussed about a year or two ago. Volt is less of an issue. With the amplifier/repeater they may be able to get into the car, but Volt Also has additional proximity checks for the Fob inside the car to actually start. WOT provided additional info previously.
I'm actually more concerned with the car and fob "talking" too much (if the fob is close) and causing the 12V battery to run down. So I DO drop my fob in a metal cookie tin when I walk in the house.
Related, I had a co-worker that used to hang up his keys next to the front door, near his car (not a Volt). One day, he left the house, unlocked the car, drove to work, and only then realized the fob was still at HOME. Had to have his wife drive the keys to him.
Edit: Here is the earlier post (2015):
http://gm-volt.com/forum/showthread...s-to-Volts-by-Bypassing-the-FOB-with-a-Gadget
I'm actually more concerned with the car and fob "talking" too much (if the fob is close) and causing the 12V battery to run down. So I DO drop my fob in a metal cookie tin when I walk in the house.
Related, I had a co-worker that used to hang up his keys next to the front door, near his car (not a Volt). One day, he left the house, unlocked the car, drove to work, and only then realized the fob was still at HOME. Had to have his wife drive the keys to him.
Edit: Here is the earlier post (2015):
http://gm-volt.com/forum/showthread...s-to-Volts-by-Bypassing-the-FOB-with-a-Gadget
cover the fob with the foil hat, problem solved
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FYI, diagrams of Faraday cages I have seen include a connection to electrical ground.
The ones with the visible threads of foil in them, that make the bag look kind of tartan, will work for this. The slightly shiny bags with an even even dark transparency are poor conductors (to enable static discharge but *slowly*). Grounding is nice, but optional and the level of mesh you need for shielding for keyfobs is pretty casual. That is, the mesh has to be smaller 1/10th the wavelength of the signal in question US keyfobs run at 315mhz, so wavelength is (3*10^8)/(3.15*10^8) = 95cm, and cage mesh needs to be smaller than 9.5 cm. Which means literally ANY closed metal basket that your keys won't fall out of is plenty. You can just drop 'em in a clean creamed corn can and they're shielded from this, open top is fine. 1/4" or smaller mesh will block that, and cell and wifi signals.
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<sigh>
The tool in question is a radio frequency "spoofer" that is, ironically, a direct offshoot of the same DECT technology that makes your wireless house phone work better.
It's not an "amplifier" (as in it doesn't make a signal stronger), it's a fast processor that sends a set of pre-known signals in a brute force attack and "listens" for a response to find the correct code.
You can basically think of the old "safecrackers" in movies who listen carefully to the tumblers while dialing a safe.
Putting your fob in a foil pouch or faraday cage won't do a thing against this sort of hacking because it doesn't involve the Fob at all (at least not for Chevrolet's design).
There is also a "replay attack" that can listen for a fob, record it, and play it back, but that happens when the fob is actively being used, not when it's just sitting around.
[EDIT: older cars are still more vulnerable to radio hacking since the Keeloq wireless entry cipher got cracked a few years ago].
Cars are in serious need of TWO factor authentication.
The tool in question is a radio frequency "spoofer" that is, ironically, a direct offshoot of the same DECT technology that makes your wireless house phone work better.
It's not an "amplifier" (as in it doesn't make a signal stronger), it's a fast processor that sends a set of pre-known signals in a brute force attack and "listens" for a response to find the correct code.
You can basically think of the old "safecrackers" in movies who listen carefully to the tumblers while dialing a safe.
Putting your fob in a foil pouch or faraday cage won't do a thing against this sort of hacking because it doesn't involve the Fob at all (at least not for Chevrolet's design).
There is also a "replay attack" that can listen for a fob, record it, and play it back, but that happens when the fob is actively being used, not when it's just sitting around.
[EDIT: older cars are still more vulnerable to radio hacking since the Keeloq wireless entry cipher got cracked a few years ago].
Cars are in serious need of TWO factor authentication.
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Bring back the coded ignition key. No crook can duplicate that with any radio gadget!! I still use it in my 2009 Chevy Equinox and I seriously doubt anyone can steal my vehicle without it.
Just take the battery out of the fob and use it strictly manually if you're so concerned. No signal to remotely rebroadcast.
Volts are fairly popular now, and I have yet to hear of one being stolen in this manner.
They've either had trouble doing so, or they're not interested. More expensive and shiny toys to target.
Volts are fairly popular now, and I have yet to hear of one being stolen in this manner.
They've either had trouble doing so, or they're not interested. More expensive and shiny toys to target.
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Ok, forgive me for a "half" hijack! On a long trips I have always brought my second set of keys and threw them in my suitcase.
I'm trying to think ahead, so if I stop for gas and run in for food I'm assuming the Fob still in my car will prevent it from auto locking? Will wrapping the suitcase Fob in tin foil prevent this from happening?
I'm trying to think ahead, so if I stop for gas and run in for food I'm assuming the Fob still in my car will prevent it from auto locking? Will wrapping the suitcase Fob in tin foil prevent this from happening?
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With my gen1, if one of the keys is in the car, it will triple honk at you as you lock the car and Walt away. Once my wife left her purse in the car and I walked up to the car with my keys in the luggage, opened the hatch, closed the hatch, then panicked when I walked up to the driver door realizing my keys ere in the back. The car was smart enough to u lock my driver door for me automatically, but I didn't notice as my habit was to press the little silver button, so I locked it. Another press unlocks it.
I don't use auto lock as I don't trust anything automatic. I like to manually do everything if at all possible.
So I don't think you have to wrap your fob in foil. On the flip side, if you lose your fob that's in your pocket, you are still locked out with the second fob in the car. But if you have an active onstar subscription you can unlock your car with the onstar app or a phone call to onstar.
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My FOB with brand new batteries is lucky to open the car from 30 ft, starting preheat is nearly impossible unless I am right on the car, very irritating
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Take the battery out of the second fob and store it in a plastic ziplock bag. If you lose the primary fob, the second fob can still start the car even without a battery (if you have read the manual).
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Any "cheap" power supplies plugged into a USB or 12 volt ports? Some of these power supplies can introduce electrical noise into the system and reduce the range of the fob receiver.
Did they nerf it between generations? Mine works from my apartment, 30 feet up, 30 feet laterally, through two concrete-and-rebar floors and a couple of walls. (Being in the elevator is too much for the fob, though, and the car can't hear OnStar most of the time either.)
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For what it's worth, I wrapped my second FOB in tin foil and threw it in my suitcase. The car didn't know it was in the interior. Once I was at my destination the suitcase was in the house, and so I had a backup if I managed to lose my primary FOB.
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No they just copy the VIN from the dash, have a key made at another location, then come back and swipe your vehicle at their leisure...
https://tech.slashdot.org/story/17/...-hacking-and-stealing-over-150-jeep-wranglers
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