Simpler solution for disabling the DCM telematics - Silencing Antennas

What does the bolded portion mean? When would the DCM commandeer the speaker away? And that energizes the relay?

 

It was my impression the car was recording data all the time, and the DCM is only responsible for sending the data. So if you drive for 6 months and then connect the DCM for a few minutes it could send all that data.

Many people live outside cell tower range. So the data would have to be stored temporarily until it ca be sent next time a connection is detected.

 

Commandeering: There are two conditions that I know of - there may be more.
When either you press the overhead console button to call Toyota or when the vehicle senses an accident and calls Toyota, this is what I refer to as the DCM commandeering the Microphone and the Speaker(s). At all other times the speaker and microphone are in the control of the radio, not the DCM, or so I understand. The speakers are commandeered away from the radio by the DCM energizing/applying a voltage across the relay coil. How the microphone connection is commandeered within the DCM I have done no research on.

 

This would not be my way of doing so, as the 3/8" to 1/2" hole through the firewall grommet and that cumbersome switch would bother me greatly, plus the hole in the fuse box. The linked product looks like it could work though; I would verify the fuse interface is indeed the correct size. Seems to me to be too much work when it is easier to just keep everything inside the cab.

Myself I would look to interrupt the power at the DCM or at the IS3 connector shown in the schematic linked in Post #166. I do not know where the IS3 connector is located. Power at the DCM is located on the large connector at the bottom of the DCM as it is mounted in the vehicle; pin #1, blue wire, lowest wire on the passenger side if you care to have a looksee.

 

This is total conjecture on my part, but I think the memory of the system would operate much like the Black Boxes in airplanes where only a certain amount of data or time can be recorded and then the old data is over written.

 

Ah OK. So basically, I can pull the DCM fuse, I won't lose my speakers, only the mic, and the DCM box will no longer be able to call home. That sounds like the best possible solution then... Why go any further? I guess unless you don't want data recorded at all.

So I do have a good amount of knowledge about this actually, at least, in regards to airplanes. The old "black boxes" used to be magnetic tape recorded and yeah they had limited memory. But modern ones can store may thousands of parameters and over 25 hours of memory. Memory is cheap these days. I mean your smartphone can have 1TB or more.

What's more, with a truck, there are way way fewer parameters to store than with an airplane. Maybe a few dozen.

I would honestly hazard a guess that the box could store a year's worth of driving data, easily.

 

Is there a memory chip or storage device within the DCM?
If so, hard to imagine anything being written when the DCM is without power.

 

So true, DCM needs power for info kept within the DCM.
jboudreaux1965 in Post #172 thinks he knows what memory chip is within the DCM.
Here is some preliminary info on that chip:Part Detail | Micron Technology Inc.
6Gb is a lot, but not excessive.

Whether any of this affects the Event Data Recorder, hasn't been discussed yet.

Edit: DCM needs power to write "new" data to the unit, it already has the old, un-transmitted data stored.

 

I’ve opted out of services via the app. My SOS button is red. That means communication error I believe. Is that it, or do I still have to press it and talk to them to opt out? I use the Bluetooth mic a lot for call, so I can’t pull the fuse without following the other thread to reconnect.

 

The more I read about this system the more concerned I get. It doesn't matter what you do as long as the DCM is in your truck, the DCM records EVERYTHING and stores it and so say the data can not be erased! Without dumping the chip on the DCM I can't really learn more about what all is stored and how to erase the data.

So even if it doesn't "call home" to Toyota all the time, as soon as it gets a signal it will upload the data and even if it never gets a signal all your data is still being stored and can be read by big brother or whoever in the future.

Man, I pretty much got out of hardware hacking over a decade ago, but this makes me want to dive into it again!

 

In a previous post mentioned that the Kyocera modem daughter board is more than likely a proprietary "black box" module, the same as Sirius/XM units.

Every sat radio has a proprietary Sirius/XM module (CAN) in it that Sirius/XM sells to the radio manufacturers to put into their products. It took us YEARS to finally hack into the XM modules. Lol, it was way harder than like sat tv!

Anyway, I took apart an OEM head unit, here is the Sirius/XM "CAN" if anyone wants to check it out. The days of TSOP's and simple BGA's are gone, be Alot harder to crack into one of these modules today...

 

I have pictures of all the circuity and chips on both sides of the board if you would like to start with that. I'm interested if there is a backup Wi-Fi or Bluetooth connection.

 

This doesn't make sense to me unless I'm misreading it. It sounds like you're saying even if you pull the DCM fuse it is still recording data.

It seems to me like either the DCM is responsible for recording AND sending data, I which case pulling the fuse would prevent data recording AND sending, or, the DCM is responsible only for sending the data and not for recording it, in which case the DCM's presence or absence has no bearing on whether or not data is recorded.

 

The unit records data. If it gets a signal it calls home. If it doesn't the data is still stored in the module and can be read later or uploaded whenever it gets a signal.

 

But how can it record data when the fuse has been pulled? It's not getting any power.

 

I don't know how a properly operating unit works and the errors it can have. It was something I was never interested in. I just want mine to not work which it does with the SIM card removed.

 

Waiting on someone who has the '24 to confirm that the DCM fuse works the same way in this new truck and pulling the fuse just disables the mic and not the speaker... Maybe I should post in the 24 forum

 

I think you should ask over there and see if someone can take pictures of their fuse box to verify.

 

https://vehicleprivacyreport.com/ put in your VIN it tells you all of the info you agreed too...

https://global.toyota/en/sustainability/privacy/on-board-cameras-initiatives/

https://privacy.toyota.com/

 

I filed a request with Toyota for all of the information they have collected on me, this is the response, so we will see