Modern vehicles are basically rolling computers. When a warning light pops up,...

https://blogfreely.net/weyladikle/do-modern-transmissions-require-software-to-diagnose-shifting-issues

Modern vehicles are basically rolling computers. When a warning light pops up, a basic code reader only tells you a small part of the story. You need professional diagnostic software to talk to every ECU and view high-speed live data in real time