With the v3 version you get an AUX input that you can use to change either limit (speed, current or power limit) or PAS without using the setup. It basically means you have the ability to mount a legalize button to bring the bike down to required max speed or power. Unfortunately there is only one AUX so you can't bring down both max speed and max power with one button.
Besides that it is like Gary say except you don't have to power down to enter the setup, the CAv3 turns off power to your bike when you enter setup so you don't have to. This makes it possible to change settings with one hand while pedaling along (may not be safe).
So you can actually do what the GM setup software does? PA strength, acceleration, top speed? Or some subset of that?
Yes, you can change everything the GM setup can except regen and reverse settings. There are settings for acceleration, top speed, maximum current (amps), maximum power (watt), low voltage cutoff, minimum speed (usable for sensorless systems), high temperature cutoff (if you install a temp probe), maximum deacceleration, amount of PAS assistance and some more. All is user changeable while on the run, but the setup is very slow to navigate trough and your throttle is unresponsive while inside the setup.
Most of this is specific to the CA v3 and wont apply to the CA v2.3 and older.
