Heavy Retrofit and Pixhawk

After completing the heavy retrofit I can not connect to the Pixhawk.
When I start QGC I get video but no comms. I upgraded the firmware to the Pixhawk with no isues, Pixhawk was plugged directly into laptop,
also I have bypassed the tether with a short-whip, currently the only thing plugged into the pixhawk is the usb to the companion computer.
Any ideas?

Can you access companion via http://192.168.2.2:2770 ? Try to upgrade it to the last version, 0.0.15.

Yes I have access and did the upgrade. Thank You
No this did not resolve the link to the Pixhawk.
I did the reboot and restarted the QGC video is up and that is all.
The FMU power is ON
The B/E led is off.
My last dive was problem free and had battery out during heavy retrofit

This is the last 2 attempts to to update the firmware from the link that you provided.

Downloading stable ArduSub firmware from http://firmware.ardupilot.org/Sub/stable/PX4/ArduSub-v2.px4
Stopping mavproxy
Flashing Pixhawk…
Loaded firmware for 9,0, size: 827916 bytes, waiting for the bootloader…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
attempting reboot on /dev/ttyACM0…
Timed out trying to catch bootloader!
Please try again.
Waiting to restart mavproxy…
Restarting mavproxy
Complete!
Attempting upload from file /tmp/data/brov2-heavy-3_5_2.params
Stopping mavproxy
Flashing Pixhawk…
Traceback (most recent call last):
File “/home/pi/companion/tools/px_uploader.py”, line 548, in
fw = firmware(args.firmware)
File “/home/pi/companion/tools/px_uploader.py”, line 115, in init
self.desc = json.load(f)
File “/usr/lib/python2.7/json/init.py”, line 290, in load
**kw)
File “/usr/lib/python2.7/json/init.py”, line 338, in loads
return _default_decoder.decode(s)
File “/usr/lib/python2.7/json/decoder.py”, line 366, in decode
obj, end = self.raw_decode(s, idx=_w(s, 0).end())
File “/usr/lib/python2.7/json/decoder.py”, line 384, in raw_decode
raise ValueError(“No JSON object could be decoded”)
ValueError: No JSON object could be decoded
Error flashing pixhawk!

Patrick is it possible that the Pixhawk needs replacing I have been through the trouble shooting pages and can’t complete the task due to PuTTY requesting a login ?
The Pixhawk is verry hot on the right side not sure if that is normal.
If the Pixhawk can be firmware upgraded then I assume the sd card is good.
This is a built and working bule rov2 purchased in February until this upgrade.
Thanks for your support

Hi @catfish, what is the status of your situation? Please contact support@bluerobotics.com if you would like to get in direct contact for some help getting back up and running.

So far it sounds like a loose usb cable between the pi/pixhawk, or your pixhawk may have kicked it. Do you see the big RGB led in the center of the pixhawk flashing?