Having Sim Card in your phone

Questions
1

It’s a dumb question, but anyways.

I always have my SIM Card in my phone.
I use Graphenos, and have the SIM Card disabled, because after updates and reboots the SIM Card disables by default.
When I need Internet, I type in my PIN for the SIM Card, use the Internet and then turn the Mobile Internet off. There’s a button for that above Wifi.
But then my SIM Card isn’t deactivated. I just turn off the Mobile Internet from the SIM, so that I don’t waste Data on background connections.

Can my location still be tracked If I have WIFI and also mobile Internet from the SIM Card off without completely disabling the SIM?
I think I can still receive SMS when I just have my Mobile SIM Internet disabled.
But when the SIM after a reboot is completely disabled, then I can’t receive SMS.
I guess they can then still track my location, because I can receive SMS.

2

Who?

3

Apparently yes, it has nothing to do with data transmission, it’s your phone pinging cell towers to stay connected to the network.

Quote from GrapheneOS FAQ:

Activating airplane mode will fully disable the cellular radio transmit and receive capabilities, which will prevent your phone from being reached from the cellular network and stop your carrier (and anyone impersonating them to you) from tracking the device via the cellular radio.

2 Likes
4

I think that if you reboot/poweron your phone, it will still automatically connect to the cell towers, even if you had airplane mode enabled when you last powered it off.

1 Like
5

I have zero information about this matter. I think its half hardware half modem firmware issue.

It depends on whether modem save modem’s last state and boot from its last state, might also depends on the boot sequence of the SoC.

However I don’t think “airplane mode” would switch off Modem on hardware level.

1 Like
6

from cell tower service providers or my ISP
The company providing internet to me when I am using my SIM Card

7

Here the Text from graphenos FAQ, which @TinFoilHat shared.

" Receiving a silent SMS is not a good indicator of being targeted by your cell carrier, police or government because anyone on the cell network can send them including yourself. Cellular triangulation will happen regardless of whether or not SMS texts are being sent or received by the phone. Even if an SMS did serve a useful purpose for tracking, a silent SMS would be little different than receiving unsolicited spam. In fact, sending spam would be stealthier since it wouldn’t trigger alerts for silent SMS but rather would be ignored with the rest of the spam. Regardless, sending texts or other data is not required or particularly useful to track devices connected to a network for an adversary with the appropriate access.

Airplane mode is the only way to avoid the cellular network tracking your device and works correctly on the devices we support."

So, yes If i manually disable the SIM, or reboot (because then it automatically gets disabled), then my cellular data provider can’t track my location if I use the phone as a WIFI Only Phone and have Airplane mode on.

When I can receive SMS, someone can track my location by using SPAM SMS or a silent SMS. - Thats’s interesting to know