I just got one of these PPC from BSR. It read codes from every possible computer in the car. The codes it read, if I'm interpreting the data correctly, ranged from my alarm being activated and which door was opened, changing wiper blades, which button wasn't working on my climate panel, my door locking problem,as well as the dreaded throttle unit. There were other codes but can't recall them.
I reset the codes and the car runs better. It idles smoother (so I think) and it also did something where my seat memory buttons now work. At this point, I'm very pleased with with diagnostic tool.
I would suggest getting this tool if you are DIY mechanic.