I was able to read 2 ECU's I had one day the next day nothing... I have tried everything I have found on this forum that other people have found to work. Tried 3 different computers, reloaded drivers still nothing. I'm wondering if I have a bad cable even with no power to the ECU Galletto says BOOT MODE INNACTIVE. I have noticed after I ground pin 24 if I keep my power probe hook on it (not applying ground) it's getting a ground pulsed to it. it doesn't seem to have a rhythm just a random pulse. sometimes one or two sometimes its held longer than others. Without trying to enter boot mode it has voltage to it. Any ideas? does this mean I'm in boot mode?

It is a dual purpose pin. in this case, an address line (irrc) that is used once the cpu is booted, so obviously you are seeing activity on the pin

Grounding the pin is done while the cpu is booting, which is when the cpu samples the pin voltage to decide if it goes to boot mode or not.

Most likely there will be a lot less activity (possibly none) on that line if it is in boot mode... until, of course, it accesses the flash (e.g. for reading/writing)