D5 light mean something coming there are 2 CAN bus interface: 1. with obd2-db9 line connect the car 2. j10 is a terminal, you can use it easily get 12V from the car, while sw1 on short route Impedance of RF trace should be controlled by 50 ohm and the length should be kept as short as possible. Battery voltage Microcontroller Power Since Version 6.2.2 text objects can contain more than one line, which will not be processed correctly with this version.