 If you're anything like me, you have a couple of old phones, just Android devices lying around. And we all know that these things have a number of radios in them, whether it be Bluetooth, Wi-Fi, GPS, or your cellular signal, just to name a few. Now, certain things like Bluetooth or Wi-Fi are easily monitored. In fact, you can get a cheap little router like this or this, or even something as cheap as an ESP chip, an ESP32 or an ESP8266, literally for under $5. And you can turn these into monitoring devices. I've done it before here at my house, where I've taken a small router like this, or again, ESP like this, and you set it up just to record when it sees MAC addresses to certain Wi-Fi devices. Doing that and logging the times, you can learn a lot about when people are coming and going. You can set up signals that when a device comes in your range, it alerts you. And this way, you just learn a lot. You know when someone's somewhere. So if you have a lot of these devices around, obviously it's easy to track. But you can turn off your Wi-Fi. You just click the little Wi-Fi icon, and it turns off theoretically. We don't know if it's actually turning off the device, but we get something we can test, the same way we'd monitor it. I can plug in one of these, or just put any laptop into monitor mode, and search for MAC addresses. And I can see whether the phone is sending out a Wi-Fi signal. I can do the same for Bluetooth. But some of the other radios may not be so easy to do, to monitor, to check yourself. So like I was saying, your cellular signal. Now on your cell phone, you can go in, and you can click the little cell phone icon, the data icon, and you can turn off data. But you're still connected to the cell phone towers, right? Because you can still make phone calls and send and receive SMS text messages, even though you have your data turned off. So it's still connected to a cell phone tower somewhere. So these cell phone companies obviously know where you are with pretty good accuracy, especially if you're connected to more than one tower, which you probably are. But you have your older devices, right? Your older devices. You take out the SIM card, or maybe they don't have a SIM card, and just deactivate them. Are they still being tracked? Does the cell phone company still know where these devices are? This is something I thought about the other day. Because even though your, you know, data plan might be turned off, or your cellular plan might be turned off, or you take out the SIM card, here in the United States, and I believe a lot of countries, it's required, all cell phones, whether you have a cellular plan or not, has to be able to dial 911. Emergency numbers, maybe a different number in your country. But if that's true, that means these devices that are non-active that I'm carrying around are still being tracked. And as I mentioned earlier, I can turn off the data if I did have it activated. But even then, I can't turn off the cellular signal. And even if I did, how do I know? So some of what I'm going to say in this video is my thoughts and theories, and I'm coming to conclusions that I may not know all the details about. So if anyone knows more about this below than me, feel free to nicely comment anything I technically get wrong that has to do with what I'm actually talking about. But can we disable the cellular device inside your phone so it's not connecting to towers anymore, whether it be your current device or past device? I think we can, and I'm going to show you how. So again, what I'm about to show you is just a theory. I'm assuming it's working, but I don't have hardware to actually test. Again, with Wi-Fi, I can put a laptop into monitor mode and sniff the air around me and detect whether my devices are still sending out Wi-Fi signals or not. I don't have anything to test a cellular signal with, but I'm pretty sure I'm disabling it. So again, these are Android devices. They're just Linux devices like any computer. They need drivers or firmware for all the devices to work. What if we were to delete the firmware for your cellular signal, for your cellular device? We can do that. And it's not just a file, you know, usually on a desktop computer, you have a module that runs or it's baked into the kernel. On Android devices, usually it's a separate partition. So if we can wipe that partition, theoretically it should stop working. It obviously stops working. If I was to do that with my current phone, which we will be doing in this video, I'm going to back up that partition. I already have the stock image in case something goes wrong anyway, but I'm going to delete the partition that contains the firmware for my cellular card inside card, cellular module inside my phone. And at that point, you know, when I turn my phone back on after doing it, I'm not going to be able to make calls, receive calls, send texts or receive texts or use my cellular data. So I'm assuming that it's not working. Now, again, I don't know if the chip might still be on its own connecting to a tower somewhere and the firmware is just allowing the operating system communicate with it. I can't say that for sure. If anyone knows more than me, again, nicely tell me in the comments, just don't be rude about it. Let's go ahead and just jump in and see what we need to do, what partition we need to look for, how to wipe it and how to put it back when you're done. So again, before we even start, here's my phone. You can see I can turn my mobile data on and off, but that doesn't turn the cellular device off. Things I'm not going over in this video are, you know, unlocking your boot loader and setting up a custom recovery, but we're going to be using all those tools. I'm assuming you know them. If not, I have videos on them, but let's get going. I'm going to do an ADB reboot to the boot loader. ADB reboot boot loader and then booting into my custom recovery of Tor. I am aware that you can ADB right into recovery, but I actually don't have a custom recovery on the phone. I have a script that pushes it over to the phone whenever I want to use it. Once Tor is loaded, ADB shell and once we're at our root shell on our phone, we're going to CD into dev, block device. On my phone, it's boot devices and then by name. It might be slightly different on your device, but it should be under dev block. And then you're going to look for a folder that says by name. In here, we're going to do a list for FSG asterisk. And in my case, I have SSG, FSGA, FSGB. And you can see FSG is pointing to, in my case, FSGA. Real quick, the reason you have an A and B and you will, for most of your partitions on modern Android devices is because you have a slot A and a slot B. In case one gets corrupted, the system is still bootable after updates. In our case, we know that since FSG is pointing to FSGA, that's the slot that we're using. Now, this device, this SSS, FSG device is actually an EXT partition. So quickly let's mount that. And I'm going to mount it just to MNT because there's nothing in that directory right now. And we'll move into that directory and we'll quickly list out all the files. As you can see, there's a lot of files and a couple of folders. Again, I'm making a lot of assumptions in this video, but if you look at the file names in this, apparently these seem like they're the firmware and or configuration for your device for different countries. We're just going to wipe it all. Again, make sure you know what you're doing and you've made backups. In fact, let's make a backup real quick before we do anything here. I already have the stock image for my phone so I can reflash at any time, but it's good to know how to do this. And there's a lot of different ways you can do it. You can use DD. Some people use ADB and Pipe DD, but you don't even need to do that. Real quick, let's have a look at how to do this one way. And again, don't blame me if you break your device. Real quick, I'm going to move out of that directory and then I'm going to unmount that directory. Then I'm going to exit back to my main computer. And then from here, I'm going to run ADB, pull, and then that block device name. So in my case, it's dev, block, boot device, by name, fsg, and then the file name you want to save it to, which I'm calling fsgbin, but I don't think the name really matters. You might want to call it fsg.mbn because I think that's what it's called in the stock firmware. And this shouldn't take very long at all. We'll hit enter and it's done already. As I try to remind people all time, because people tend to forget this and it makes things a lot simpler, is that on a Unix or a Unix like system such as Linux, everything's a file. So even though this is a partition on a hard drive, the computer sees it as a file. And all we did was ADB pull like you would any other file, but we pulled the whole partition to a file. But let's check it real quick with file. So the file command will just tell us what type of file a file is. So all we do is type in the file, the name of the file we just copied, and when I hit enter, it will tell us that this file is a Linux EXT file system. It gives us the UUID for the partition and even tells us the value name is SSG. So everything seems good so far. Going back to our ADB shell, we can now mount that partition again. Mount, dev, block, boot device, by name, SFG, forward slash MNT. We will move into the MNT, whoops, directory, and we will do the scary thing of RM-FRASTRIC. And we just deleted everything on that partition. At this point, we will reboot our device back into the system. And after my cool boot animation, I will log in, show you that I no longer have any bars. And if I pull this down, it says mobile data no SIM card. And I can't turn that on or off. So we successfully did it. We basically made our phone not a phone anymore. We removed all the drivers so that it's no longer interacting with that cellular device. Again, I don't know if that cellular device still on its own is connecting to a tower. That's beyond my scope of abilities to check. But it's no longer interacting with the operating system. So I'm assuming that it's not talking with towers anymore. Because I cannot make a call. If I try, it just tells me cellular network not available for voice calls. Texting and data no longer works either, which is what we were going for. Now, again, this is on my main device. But theoretically, if you're using one of these, you know, a phone that isn't connected to a service anymore, and you want to disable that, this is something you want to think about. Because even though you don't have service, you are still connecting to cell phone towers for emergency calls. Again, if that's something you're worried about. Now, real quick, you probably want to fix it so that you can make phone calls with your phone again. Let's have a quick look at that. ADB reboot bootloader. And once your phone is at the bootloader, we can use fastboot to push over that image we had copied earlier. Fastboot flash FSGA or B if you're using slot B. And the name of the file that we pulled earlier. Only takes a second. And now I can reboot the phone. You cross your fingers that that image you made works. And that when your phone reboots, you can make phone calls. Notice once again, we do have our cellular bars and we also have our Wi-Fi symbol, which I'm realizing was gone too. So we're actually disabling Wi-Fi as well when we're doing this. I can now turn my Wi-Fi on and off and my mobile data on and off and Thank you for calling NCI. I can make phone calls. So we did it. We completely disabled some of the radios on our device, at least as far as software is concerned again. I know I've said it like five times in the video. I can't test to see if the device is still communicating with the tower and it's just disconnected from the OS because you don't know what these devices, you know, the firmware that's actually embedded in devices doing. If you know more than I do, feel free to comment below. But we successfully did it and put it back. Again, when I did it, I wiped the entire partition, which also disabled our Wi-Fi, which you may or may not want. You might want to go through those files one at a time and try to determine what each one does. I'm sure there's probably documentation online. So if you wanted a Wi-Fi only device, but you wanted to disable the cellular feature, I'm sure you could do that by deleting the proper files and then pushing them back later on. And again, I showed you how to pull certain partitions. So that's always a good thing to have backups of your partition. That's one of a few different ways to do it. And also it's always good to have some stock ROMs around if you're if you can get a hold of them or make your own. So that's it. Again, what do you think? Is this something that you might find useful? I'm sure there are people out there who probably would. Is this something you've thought about? Because again, for me, with the older devices, I know that they have Bluetooth and I know that they have Wi-Fi and I know that those things can be detected. But I wasn't even thinking till recently that even though there's no service or even no SIM card in here, that they are still talking with a tower. So they're still being monitored because everything has their own MAC address or some sort of serial number on them and they're communicating with whatever they're communicating with those numbers. So it's very easy to go, oh, at the very least this phone was connected to this tower so they're in this range. But if you connect to more than one tower, the more towers you connect to, they can pinpoint your location pretty good if that's something you're concerned about. I'm not paranoid like that. This is just a thought thing for me. But if you ever wanted to have a device that you can keep notes on or do other things with or you want to take it offline for a certain amount of time, you now know how to do that. Anyway, I do thank you for watching. If you enjoyed this video, be sure to like, subscribe and share this video. My website is filmsbychrist.com. That's Chris the K. There is a link in the description. So check that out. You can search through all my videos there. I've been doing this for years. I have thousands of videos and I appreciate you watching. And I hope that you have a great day.