2004 GT convertible....my brake light on the dash will not go off. It usually only came on when the e-brake was on. Then is started to stay on intermittenly...now is will never go off. Is there a sensor somewhere? Thanks
Check the fluid level in the master cylinder. If it is low, it will make the light come on. If not, and your brake pedal feels fine, the problem is probably the switch on the ebrake lever. It's not very expensive or hard to change, but you do have to remove the console or at least the console box liner, depending on the car. I've never been there on an 04, so I'm not sure exactly.
My 99 cobra had the same problem - it was just low brake fluid in the master cylinder. the fluid sloshing around trips the sensor, which was causing the light to flicker.
If thats not it, then I'd check the e-brake as well.
Check your pads. I have been told that the sensor in the resevoir is set so that it comes on when the pads are shot because the wheel cylinder volume increases as the pad wears, using more fluid. That light came on in my cobra EXACTLY when the pads were toast.