Jetson Nano 2 GB Developer Kit "PT: Partition TBC NOT found"

So I bought the 2GB Nano DevKit today and it worked fine the first time. I was trying to install the newest JetPack for the 2 GB version but the installer window disappeared at the last step before I could start installation, so I just disconnected the power. It rebooted fine but I ran out of time then so I had to power down the board again. After that it stopped booting at all - constant black screen.

I reflashed the SD card (SanDisk Ultra 32 GB) 5 times already - 3 times using Etcher and 2 times using Win32 Disk Imager. Also tried another SD card twice (random 16 GB Kioxia). Nothing works. I’m using a 3.1A 5V USB-C power supply.

Here’s the serial console output:

.
[0000.163] [L4T TegraBoot] (version 00.00.2018.01-l4t-e82258de)
[0000.168] Processing in cold boot mode Bootloader 2
[0000.173] A02 Bootrom Patch rev = 1023
[0000.177] Power-up reason: pmc por
[0000.180] No Battery Present
[0000.182] pmic max77620 reset reason
[0000.186] pmic max77620 NVERC : 0x40
[0000.189] RamCode = 1
[0000.191] Platform has DDR4 type RAM
[0000.195] max77620 disabling SD1 Remote Sense
[0000.199] Setting DDR voltage to 1125mv
[0000.203] Serial Number of Pmic Max77663: 0x172aed
[0000.211] Entering ramdump check
[0000.214] Get RamDumpCarveOut = 0x0
[0000.217] RamDumpCarveOut=0x0, RamDumperFlag=0xe59ff3f8
[0000.222] Last reboot was clean, booting normally!
[0000.227] Sdram initialization is successful
[0000.231] SecureOs Carveout Base=0x00000000ff800000 Size=0x00800000
[0000.237] Lp0 Carveout Base=0x00000000ff800000 Size=0x00000000
[0000.242] BpmpFw Carveout Base=0x00000000ff800000 Size=0x00000000
[0000.248] GSC1 Carveout Base=0x00000000ff800000 Size=0x00000000
[0000.254] Resize the SecureOs Carveout to 0x00100000
[0000.259] GSC2 Carveout Base=0x00000000ff900000 Size=0x00100000
[0000.265] GSC4 Carveout Base=0x00000000ff800000 Size=0x00000000
[0000.271] GSC5 Carveout Base=0x00000000ff800000 Size=0x00000000
[0000.276] GSC3 Carveout Base=0x00000000bf800000 Size=0x00200000
[0000.282] RamDump Carveout Base=0x0000000000000000 Size=0x00000000
[0000.288] Platform-DebugCarveout: 0
[0000.291] Nck Carveout Base=0x00000000ff800000 Size=0x00000000
[0000.297] Non secure mode, and RB not enabled.
[0000.301] BoardID = 3448, SKU = 0x3
[0000.305] QSPI-ONLY: SkipQspiOnlyFlag = 0
[0000.308] Nano-SD: checking PT table on QSPI …
[0000.313] Read PT from (2:0)
[0000.328] Using BFS PT to query partitions
[0000.332] PT: Partition TBC NOT found !
[0000.336] Warning: Find Partition via PT Failed
[0000.340] BoardID = 3448, SKU = 0x3
[0000.343] QSPI-ONLY: SkipQspiOnlyFlag = 0
[0000.347] Nano-SD: checking PT table on QSPI …
[0000.352] PT: Partition TBC NOT found !
[0000.355] Warning: Find Partition via PT Failed
[0000.360] Error is 1

Did I break the board somehow? Is there any fix possible?

No, you are not breaking the board.

Please use sdkmanager to flash the board and it will be fine. This is a known issue.