How-To: Cell Comm Killer.

[Diboblo]

Sierra AR7552 User/Installation Manual

View attachment AR7552-2647456.pdf

 

[Lilschmied]

Better photo of the guts of the AR7552 card, heat spreader off, courtesy of the FCC:
View attachment 133878

Of course that Qualcomm chip doesn't exist on their website...

 

[HotWheels22]

The effort is ongoing! I'm bouncing a few questions off of a career expert in antenna design and radio transmission, as he has time. The attempt to shield the entire card is on-hold until I get a few more questions answered.

 

[Diboblo]

Had a thought, while braving the heat, at the shop... All of this tinkering woud be moot, if we find and removed the SIM card.

Just throwing it out there.

I did a small amount of research and some manufacturers use a dongle, inside the dash, that accepts the SIM. After it cools down a bit, I'm going to remove the glive box and poke around, in the dash.

Food for thought.

Hemi Rocket Barge

 

[fumanchu182]

Had a thought, while braving the heat, at the shop... All of this tinkering woud be moot, if we find and removed the SIM card.

Just throwing it out there.

I did a small amount of research and some manufacturers use a dongle, inside the dash, that accepts the SIM. After it cools down a bit, I'm going to remove the glive box and poke around, in the dash.

Food for thought.

Hemi Rocket Barge

Had my dash apart. Didn’t find a sim chip on my 2015. Maybe embedded in the stack?

 

[HotWheels22]

Had my dash apart. Didn’t find a sim chip on my 2015. Maybe embedded in the stack?

Same for the 2023. While the card is different between the 2015 and 2023 (different gen cards, both Sierra AFAIK), from everything I've been able to find, the sim's embedded on the AR7552 card. Photo below is the guts of the 7552 that does the actual transmission.

You're 100% right that if we could locate a separate SIM that would be ideal, but haven't found evidence that exists. If you find other data that suggests otherwise, would be very interested to hear.

 

[Lilschmied]

Had my dash apart. Didn’t find a sim chip on my 2015. Maybe embedded in the stack?

They should have an eSim so no physical component to remove unless it's just a flash memory chip which probably breaks other things.


Even without a sim, you can ping a tower for emergency services you're just not registered on a provider to receive calls. The IMEI still identifies your unique modem.

 

[Lilschmied]

Has a anyone tried removing the antenna jacks from the sierra board? That little stub would act as an antenna. Short of wrapping the board in a complete faraday cage I don't think there's a good way to kill cell without disabling the chip by yanking it or killing power to it.

Maybe some paint:

 

[Diboblo]

Has a anyone tried removing the antenna jacks from the sierra board? That little stub would act as an antenna. Short of wrapping the board in a complete faraday cage I don't think there's a good way to kill cell without disabling the chip by yanking it or killing power to it.

Maybe some paint:
View attachment 142437

Yeah. For MY17+ vehicles, powering down the card may be the solution. Probably a lot more work than most want to engage in, but if you value your privacy, it's a small price to pay.

Hemi Rocket Barge

 

[2ndgen]

So what exact MY did this change happen that the simple blocker design is no longer sufficient? before 2017 or after 2017?

 

[Diboblo]

So what exact MY did this change happen that the simple blocker design is no longer sufficient? before 2017 or after 2017?

MY15 MY16 simple FAKRA D dongle disablesall cellcomms.

MY17+ has 2 antennae (violet and pink) and a suspected onboard antenna. After both ports were blocked, the Sierra card still maintained a signal.

There are three wires, on the board: Grey, Black and White. Remove these and disable the cell. You would need to use shrink tube on the end of each wire, before applying power.

Hemi Rocket Barge