I pulled the fuse on my car's DCM. Cost me a speaker that is on the same fuse, and of course Bluetooth etc, but I don't care about that. No check engine lights, easy to reverse if needed. But this depends on each model of car.

[–] gastroglizzy@piefed.social 22 points 1 day ago (1 children)

I'm happy to help just for the love of the game.

The data is transmitted via a radio signal of some kind. That radio signal is created by a transmitter. Stopping the data transmission is a matter of finding and destroying the transmitter or its ability to operate.

The exact "how" depends on the make and model, but in general, removing or destroying the antenna is probably going to be the easiest way, but this usually results in destroying all the radios in the car. You'd probably still have Bluetooth, aux, CD, tape, whatever, but AM/FM, satellite, OnStar, and similar would probably be broken also.

If you don't care about concequences, you can do that yourself with an angle grinder in a few minutes. Hopefully you don't create any leaks you can't fix with a tube of blue RTV (yes, color matters, blue is for marine/water).

If you're determined to keep the other radios working, you would need to do some research to determine how your specific model "phones home". Most commonly, this is via 3G, but other solutions exist. From there, it's a matter of destroying, removing, or short-circuiting whatever component controls that radio.

[–] Hirom@beehaw.org 8 points 1 day ago* (last edited 17 hours ago)

Bluetooth range is too short. AM/FM frequencies are regulated so that individual cannot legally broadcast. So these probably aren't used to send data to manufacturers.

They're probably relying on existing channels that are IP capable, have good coverage, have relatively cheap antenna/MoDem available on the market. Such as 3/4/5G, Wi-Fi, LoRa.

Disabling those likely mean loosing features, ie emergency calls, anti-theft localization... But it may be the easiest way and can be an acceptable compromise for some. Flashing devices to keep using the hardware and features with more trustworthy software is potentially better. I fear regulators/vendors would put roadbloacks. All onboard systems may require some kind of certification to be street legal. If software certification is necessary, then hobbyist couldn't possible pay for that, which means in practice hacking you own device may not be legal. If there's an accident, except insurances to use any unauthorized car modification to put the blame on you and deny coverage.

[–] slacktoid@lemmy.ml 14 points 1 day ago

Sniff for mobile network radio signals. And keep pulling things out till that stop, then keep putting things back till the car starts working as expected. Simple as bruv /s