We are useing Freematic I2C readers for remote diagnose on Fiat Ducato (CAN 29/500).
Sometimes it happens that car report some warnings on driver screen. We have also a case that car did not start and it turn off the engrine on motorway(did not recognize the car key).
I have a similar problem. My system is not Arduino but STM32 board (3.3Vcc). 5V -> not connected ( have a 3.3V on STM32 board) GND -> connected with GND board White -> SDA (board working on GND to 3.3V level) Green-> SCL (board working on GND to 3.3V level)