Because you pushed the brake. I think you need to rephrase your question.
You can access the middle brake light from the inside of your 2000 Dodge Neon cargo compartment. Remove the brake light wiring harness. Remove the brake light retaining bolts. Reverse the process to install the new brake light.
The brake light switch, on a Dodge neon, can be found under the dashboard just below the steering column. The brake light switch just unplugs. Unplug the switch and replace with a new one.
A Dodge Neon use DOT3 brake fluid.
Bad fuse or bad brake light switch.
Master cylinder low on brake fluid or parking brake not totally released
dot 3 brake fulid
In a 1998 neon (first generation) the tail light, brake, and blinker (turn signal) use one bulb with two filaments.
Either you're low on break fluid OR your parking brake is set. In either case, it must be repaired.
There is no brake light sensor. There is however a brake light switch. It may be mechanical, which would be located somewhere on the brake pedal lever. It can be bad or just out of adjustment. It can also be a pressure switch located on the master cylinder.
You need gas!.... or your fuel level is very low, my 2000 Neon a chime will also sound.
You might need new brake pads or rotors depending upon how worn down your brakes are. I have a 2003 Dodge Neon SXT and I had the front brake pads replaced for $140.
Haynes repair manual, Dodge Neon 2000 thru 2003. Book #30036