2001 Kia Sportage Brake Warning Light

My 2001 Kia Sportage Brake Warning Light stays on most of the time. I have tried checking all of the brake pads and the fluid levels. Any ideas what may be causing this.

If topping the brake fluid does not help, and after testing the level switch for any problem, consider the following:

1- THere is a switch on the hand brake: is there any obstable preventing the hand brake to rest in fully recessed position? Is the switch positioned correctly? (loosened, shorted wires.)

2- Does the pedal slowly goes to the floor if you keep pushing when stopped ? A leak or failed master cylinder will cause that and pop the brake light.

3- Auto adjust for rear brakes operates when braking backward only and if brake is always used softly in reverse, brakes do not adjust and take more and more travel to apply and while front pads are always tight, it takes more travel to apply the rear and this mismatch causes BRAKE light to come ON" . HOwever generally it turns off after brake is released.
You can provoque auto adjustment or rear brakes in the following manner:
find a place where you can back-up 10-15 feet without danger.
Engage in reverse, accelerate then brake hard to a stop
FOrward where you were and repeat 10 times. After this operation, you will probably feel the brake pedal travel has shortened.

I will try these ideas tonight and post results if they work. Thanks for the response.

All it took was to top off fluid. There is a line on the side of the master cylinder and it was above that line so I figured it was good. Thanks for the help.