Innova 3100j Diagnostic Code Reader / Scan Tool with ABS and SRS for OBD2 Vehicles
OBD2 scan tools work on most cars 1996 and newer. The parameters you can look at will depend on your particular car.
Note that you must take care of the underlying problem before switching off the light for some malfunction, otherwise the light will just come back on.
These tools are useful for repair diagnosis. You can do the actual repair yourself (if you can) or have someone do it for you.
Please educate other SD members with your experiences with these or other scan tools.