I have an autonomous vehicle that I am building, it is powered by a 12V battery (or 20V AC adaptor) that powers a NVIDIA Jetson Orin Nano, which then powers via USB->USBC ESP32 devices. I also then have a 24V battery that powers a motor controller, which connects into the ESP32 for PWM signals. The motor controller has three digital connections (6V/GND/PWM Signal). To get this to work properly, I have the grounds from the motor controller connected to the ESP32 ground that is sending the PWM signal. I believe this ultimately ties the grounds between the two power sources together, but I also have the grounds connected to a common ground bus.
Everything seems to work fine and haven't smoked any components - but anytime I am plugged into an external data source (charging one of the batteries or using the power adapter for the jetson) I am triggering a circuit breaker in my room. I can't tell if its just happening randomly and using too much power or if it's because my wiring of the vehicle is causing this.