Modern cars are basically networks of rolling computers. When a dashboard light...
https://zaneznae304.lucialpiazzale.com/what-is-an-ecu-in-a-car-moving-beyond-guesswork-in-modern-repairs
Modern cars are basically networks of rolling computers. When a dashboard light pops on, a cheap code reader only shows you a vague surface fault. To actually fix the car, you need software that talks to every ECU and tracks live data streams