Phone keeps restarting randomly and Wifi/BT not working

Hi Ed,

Thanks for including the panic log; that's exactly what's needed to debug boot loop issues like yours.

In your case your panic log has the smoking gun right here.

"panicString" : "panic(cpu 1 caller 0xfffffff035e546c8): SMC PANIC - ASSERTION FAILED: target/d16/target.cpp:263: 0, SMC BSC failure, spreadsheet ver(*10) 190
S.sensor array 0 - 6 is 0x0, 0x400, 0x0, 0x0, 0x0, 0x0, 0x0

iFixit has a new Wiki page specifically devoted to SMC PANIC - ASSERTION FAILED errors, as that's how most of them are now logged on iPhones starting with the 13.

iPhone SMC Panic Assertion Failed - iFixit

According to the best information we have available, here's the source of your problem.

iPhone Model Sensor Array Likely Issue
iPhone 13 Mini 0x400 Gyroscope (located on the bottom board)

The bad news here is the part that's causing the looping is located on the bottom board of the sandwich board assembly, and as such is going to be extremely difficult to repair. Here's a quote from our resident expert Alisha ( @flannelist ).

The unfortunate part is that the sensor in your panic points to an issue with the logic board. The x400 sensor is specific to the iPhone 13 mini. The logic board for any iPhone X or new (save the XR and the 2020 and 2022 SE variants) has a stacked logic board. It's really two separate boards sandwiched together.

The x400 sensor is on the bottom board. Usually something like that would be caused by bend, or substantial drop. There could be a break in the connection between the boards, or an issue with the bottom board itself. That will require soldering and some very specialized tools to repair.

That came on a question from another user with the exact same problem.

iPhone 13 mini restarting, SMC PANIC - ASSERTION - iPhone 13 mini - iFixit

Another user stated that they had the same problem and that changing the charging port flex cable assembly fixed the issue for them. Unfortunately they didn't provide any details so it's not clear if by "same problem" they meant they had the 0x400 error code, or just that their phone was rebooting. If the latter, then it's likely not really relevant.