Have you tried removing your Photon/Electron/RedbearDuo from the Carloop and check to see that the microcontroller works on its own? When on their own, you can power these from USB.
If the microcontroller does not work on its own, then check the community forums dedicated to your microcontroller.
If your microcontroller is working, then the most likely thing to look at is the voltage regulator and power protection circuitry on your Carloop. Since both GPS and the CANbus stopped working, I would assume a power issue.
If you have some electronic skills, you can test your Carloop circuitry. The circuit information is on Github:
Take a look at the board and schematic files for v2.3.
If there is a hardware problem and you find it, it should be possible to change the faulty parts by hand soldering, so long as you have a little bit of skill with SMD soldering.