Though there are different models of wireless controllers for PS2, the primary functions and features are same. When you buy a wireless controller, at first, you should check the package. There should be a controller, a receiver and perhaps some batteries. Most controllers use AA or AAA batteries.  Then, the receiver should be plugged into the controller input port on the PS2. Now, turn on the wireless controller. Some wireless controller may turn on automatically, some should be pressed any buttom to set up, and some models have a separate power switch, which should be clearly labeled.

What is the limitation of the PS2 wireless controller?
Most PS2 controllers are powerful enough to provide more than enough range to be practical, so you should check the specifications of any model before you buy it. This is particularly important if you have a very large television and TV room, because the weaker wireless controllers may end up forcing you to sit closer to the TV than you usually do.

How to protect the PS2 wireless controllers?
It’s important to keep the buttons and contacts of the wireless controller clean and dry. Dirt and moisture can cause sticking buttons and poor controller response. Besides, you should pay more attention to the replacement of batteries. The lifespan of the battary varies according to the controller itself and the brand of the battery. Be clear  that the rumble feature uses the most battery power. If you want to get the most life out of your batteries, consider disabling the rumble feature on the controller. There should be a clearly labeled switch that allows you to do this.
It’s also important to consider how your controller powers itself off. Most controllers will automatically turn themselves off after a few minutes to save battery power, but some must be turned off manually.