my brake light is on. i have plenty on brake fluid now i did not have enough before. so do i wait or? i pumped the brake panel plenty of times. not too much of an improvement. the brake light is still on. the brake pedal still goes real close to the floor. what would it be?

you must bleed the brake system. Get someone with heavy feet to do the stompin' on the brake. capture the brake fluid with a small piece of tygon, (aquarium small) tubing into an old bottle, and note the amount, as you loosen the bleeder (and you can see with clear tubing the bubbles) tighten the bleeder, and command the big boots to press the pedal once again. Do it four times, so you need to refill the reservoir (don't get carried away and have to do it all over again)....do both sides, and the rear too-

...I mean, yes there could be an internal leak IN the master cylinder, but sounds to me like someone has been doing a bit of brake work and didn't bleed the system properly....hate to put you thru all this jiggamaroll for nuthin'

question remains, why was the level so low, and the answer is, your brake pads are in need of replacement, because that brake fluid WAS in the reservoir, NOW it's in the calipers! see if there is at least 1/8 left on the pads...now's the time, while you're grobblin down on that-

I have replace both wheel cylinders on the back brakes and both brakes on the truck and bleed the brakes, now the brake light came on and wont go off. I took the battery cables off still on.