TK1 fan turns on but otherwise unresponsive

Hi All,

I have a Jetson TK1 that I didn’t use for a while, and then when I tried to use it recently, I got no HDMI output. Next I tried to connect using the DB9 male connector, using an FTDI USB to Serial chip with the RX/TX cables crossed over (null modem cable configuration). DB9/RS-232 Pin 2 = RX, Pin 3 = TX, Pin 5 = GND.

I have repeatedly reset the Jetson TK1 but see nothing coming over the serial.

From my macbook, I am using the program picocom, specifically: picocom -b 115200 /dev/tty.usbserial-A505C7TQ

I can see the TX indicator LED’s light up when I send data over, but the RX indicator LED’s remain dark.

Is there a way to re-flash the Jetson TK1 in this state? I expected to see some sort of bootloader but since I see nothing, I am worried that the board has been irreparably damaged. The board warms up when I disconnect the fan, so the SOC is clearly still consuming a decent amount of power. Any suggestions on how to further troubleshoot?

If you put the TK1 in recovery mode, is it detected as device from host with lsusb ? If yes, you should be able to reflash. You may clone the APP partition image to host before if you have some important data.
I think on TK1 you would have to enable HW flow control for serial console (and use a full wired cable).
Furthermore, if you have a USB keyboard, does Num lock LED works 30s after boot ?

Thanks - I will try your suggestions (need to find cables and keyboard w/ led indicator). Pin 7 on the DB9 male connector is +6V with respect to Pin 5 GND. All others are 0V. Pin 7 should be RTS (Request to Send), so maybe there is hope with the full Null Modem Cable & HW flow control.

In some cases, it may be just a video mode misconfiguration. Are you using a different monitor or cable (adapter ?) than before ? Probably at least DVI or HDMI monitor is required able to send EDID…a VGA monitor may not work.

If your TK1 is connected to Ethernet network, you may also see the DHCP request in the DHCP server logs…then you may try to ssh into the TK1.