2001 brake light problem

I have a 2001 Chevy Impala that has recently started having a problem with the brake light. After driving the car about 10 minutes the red brake light comes on and starts dinging. My husband checked the brake fluid and the brake pads both were fine. Any help would be greatly appreciated.

Just guessing but it could be an ABS/Traction Control issue [damn computers, lol]-- When was the last time you checked tire pressures? Left to right pressure imbalance may "trick" the ABS system into thinking that either a tire is going flat or one wheel is getting less traction than the other -- this is because a tire with less inflation presssure will actually have a slightly smaller rolling diameter [will roll faster] than one with a higher pressure.

You may also have to reset the low tire pressure warning after making sure that all pressures are equal. Key ON, Radio off, hold "DISP", etc...

If the light comes on when you're not "on" the brakes, the above is probably correct -- it the light comes on when your are applying brake pressure, the rotors may be worn too thin and the system may not be able to compensate, or there may be air or moisture in the hydraulic system and the brakes need to be bled.