Redd

It isn't unique to RF chips. Ages ago, when a "nine volt" four(?) transistor AM radio was about all you could use without a power cord? I had a dead battery, no spare available, and had put the radio away in a drawer until I could get a new one. One afternoon there was an incredible lightning storm, and what do I hear, music coming out of my drawer. Damfino, but the radio received and absorbed enough power from that storm to start playing music again.

Like the "meat stickers" on supermarket meat packages, and the stickers behind library book pockets, all the RFID chips absorb energy and then re-emit a small part of that. Same way that the toll passes on windshields work. Doesn't matter if they are only 2% efficient, they can absorb and consume almost all of the tuned signal that hits them, and the short "peep" they send back is enough for the wall(car)-powered receiver someplace to hear them.

To me it would make more sense for the CAR to be doing the pinging, than to have the key fob doing it so often. If the fob can still get two years of coin cell battery life while peeping away, CERTAINLY the car could afford to use that much power??

Waggin

No gigantic box needed. https://www.wired.com/2017/04/just-p...can-steal-car/
You go to eat out in a restaurant. One thief stays by the car, trying the door while the other one just walks near you with the other box in his pocket. Most time, they just use these to steal stuff from the car, but given a little more time, they can steal the whole car of course.
I just have the keyless entry turned off on mine. I have to press the fob button to unlock.

Redd

"No gigantic box needed."
In the US, and I suspect elsewhere, we have valet parking at restaurants, hospitals, and other places. And there is always a "valet stand" where the keys are kept, receipts, etc. which would have plenty of room for a very large radio to be stashed in it, by just one corrupt person. Which would then capture every keyless entry car, every day, all week long. A notepad or some phone pix with license plates and timestamps...voila, many good codes and cars to be had without "approaching" anyone.
Thieves are clever.

Turning off keyless entry?? Is that just an MMI option, something new, or do I need to look at my primitive AMI menus to find that's in there too?

superswiss

I think this horse is kinda dead by now. Those who are truly worried about this should take measures. I don't live somewhere where restaurants and stores have parking lots. My car is usually parked somewhere different from where I am. A thieve would have to be specifically interested in my car and follow me. Otherwise it'll be completely random for somebody be even close to my fob and as I said before, at home I park my car in my garage out of sight. I think there are simple steps that can be taken to reduce the odds to nearly zero to be the victim of such an attack.

superswiss

Bringing this thread back. I don't wanna restart this whole discussion, but I figured this would be of interest to some of you. I recently took delivery of my '19 C63S Coupe in Germany and I just became aware that apparently both BMW and Mercedes have addressed this security vulnerability by adding motion sensors to their latest key fobs. My car being a facelift, it has received the updated key fob, but I haven't been able to verify this personally, because my car is currently on a ship heading to the USA. Somebody on MBWorld just tried it, though, and it appears to indeed work. He left the fob on a box next to the door handle and tried to unlock the car 10 minutes later and it didn't unlock. He then put the fob back in his pocket and tried again and then it worked. Supposedly once the key fob doesn't detect any motion for 2 minutes it stops sending out a signal until it detects motion again. I will have to try this on my car once it arrives here to make sure mine has this feature. But also, with the Mercedes fob you can double tap the lock button in rapid order and that deactivates the keyless feature until the unlock button is pressed. So MB addressed this issue in two ways. The latter is also meant to safe battery in the fob if it's not going to be used for a while. Kudos to BMW and Merc to step up and address this issue, but Audi continues to be missing in action on this subject and further falling behind in certain areas. There's hope that they'll follow suit and implement similar measures.

-=Hot|Ice=-

I use to for like a year. Then it just got annoying taking it out of the case. I put it in my backpack now. BMW and Mercedes have both indeed resolved this issue.

heymoe

I just disable the key-less entry feature so you have to push the unlock button on the fob. Not a big deal for me since I've been doing it this way for the last 15 years with my A6