This is what you are looking for: https://youtu.be/pA0zYTmi5ck

You could get yourself a RF analyzer or an old Hammy (Ham radio enthusiast would likely have something you could borrow)and find out what they are using then that would allow you to figure out your options such as removing the antenna, sim card, or the module in some manner. The problem with removing modules could be they are tied into the cars electronic controller which could cause issues with the car even working.

Drive older cars and learn how to fix them!

We need an online guide, based on make and model, on how to disable the transmission of this data.

You really can't

Also don't start breaking your own car like some of these comments suggest. It can go wrong in many ways and may even harm the value of the car.

As long as you have a Google or Apple phone in your pocket... The car will actually not gather much more than your phone already does... So don't overthink it.

I recently bought a 2021 vehicle that has OnStar. I knew this would be a concern, but luckily there was a guide online to replace the antenna with a dummy antenna that isn't ever able to connect to the network to send data.

So that might be an option! It's still collecting but it's not sending anything back.

My solution is to continue to only own old (mid-2000s or older) cars in perpetuity.

(And also use a bicycle instead for most trips.)

I think the only good way to go is to break the transmitter inside the car and hope it doesn't brick it.

You cannot stop the collection. It ALWAYS collects. It may not transmit, even if connected. For example the black box in many cars is really an assortment of ECUs that contain fine grained historical data. It does eventually roll over and get replaced but the data is there.

For example there are public cases you can find where the police, not even needing a warrant, were allowed to dump this data off of a rental vehicle that a suspect, not convicted just suspected, was thought to have been in. Of course the copaganda story showed that they the used this data which was mostly location by gps and speed by the wheel sensors and gps to get a track of everywhere that vehicle had been in the last 6 months. Every person who rented it and drove it somewhere had their privacy violated. But I guess that's normal now.

The infotainment systems are the biggest jerks for data storage as they're just mini generic computers today with lots of storage.

To stop wireless transmission you can remove the sim card from the modem. Many vehicles won't work or even start if the modem is disconnected (unplugged or unfused). A Nissan for example will drain its 12v battery overnight trying to find the modem if it is unplugged. But if the sim is bad or disabled, it will try and fail to communicate, then retry later which won't kill the battery.

You lose a lot of convenience and the data is still there. So the answer is basically you can't drive a new vehicle without it violating your privacy with collection. You can only make the wireless transmission more private or disabled. I suppose you could buy a scanner yourself and before you leave the vehicle, factory wipe all ECUs. But even then you'll need to enable them for emissions testing and such if that's in your area.

Off topic. I saw a few comments about disabling or removing the modem on the car. How about removing where the telementry code resides in? Is that feasible?

The situation here is rather bleak really.

Generally these cars have their own always on cellular data connection paid by the manufacturer. So they don't depend on. Your phone for anything.

What they do is record and transmit any sensor data they can. The sexual activity you mentioned, comes from the sensors in the seats that are required to activate seatbelt warnings, or disable the airbags if a child is in the seat. Data from those pressure sensors can be used to determine if there's a certain kind of rhythmic motion happening in a given seat.

They also collect any and all data they can from devices they connect to. Like phones. So don't use carplay, or android auto. Don't use their app. When using Bluetooth audio don't give permissions to make calls or access contacts.

It should be possible to physically disable the onboard cellular radio. That will prevent any live data tracking. Exactly how depends on the specific car you're looking at.

I would assume the dealer can access and download the data manually. Use private non-dealer repair shops for any regular maintance or any repairs possible.

Number 1) find the fuse that controls the modem and pull it. Without this your car can only report when the service techs hook it up to their diagnostics, and what is reported there versus what reports on the regular from the modem is a huge difference. You lose a lot of convenience this way, but that’s to be expected. CarPlay and auto give you a lot of that convenience back, but now you’re giving a lot of that same data to Apple and Google, even if all you think you’re doing is projecting maps from your phone to your infotainment. Do you trust them? You can use Bluetooth audio in most cars without using CarPlay or auto, that should be safe. Stick to maps on your phone if you don’t want Google or Apple getting your driving data.

If buying new, I believe you can ask to have the modem removed from the vehicle, which wouldn't allow your car to access the internet. Haven't had the opportunity to try this myself yet, but very much plan on it for whatever vehicle I purchase new in the future.

Not the exact (and only) solution, but some manufacturers may have a Do Not Sell My Information request form. Subaru has it on their website and I submitted a request for myself. Obviously we won’t know if they actually follow through, but it’s worth a shot. Some people have experimented with going in and actually disabling the antenna that the car uses for telemetry, but that’s at your own risk and likely voiding warranties in the process.

I think using carplay/android auto isn’t as bad since the infotainment system is just projecting your phone’s display, so your phone’s privacy policies apply. Whether you trust those policies is of course up to you. Cars that force their own systems (like GMC I think) are more risky because you are using it directly.

If you drive a Toyota and the infotainment system has a "DCM" icon in the corner, your driving habits and location are being recorded to their servers.

E: this is happening via their own cellular modem built into the vehicle, with its own separate SIM or eSIM. Getting at the module seems to require access behind the dash, almost purposely making it difficult. Pulling the fuse will kill the front passenger-side speaker, though there are YouTube vids on how to reactivate the speaker while keeping the DCM module dead.