It sounds like you have a faulty brake light switch.
The switch is probably stuck on the pressed on (circuit complete) position all the time and keeping the light on.
The brake light switch is located on the brake pedal bracket. When you depress the brake pedal it pushes against the brake light switch and the lights illuminates. There few ways a brake light switch can fail. It can simply have a burnt component and not make connection to turn on the light or it can fail being stuck on the 'on' position.
The brake light switch can be changed easily using simple hand tools.
Here is a helpful video:
I have attached diagrams for your reference.
Please let me know of any questions.
Images (Click to make bigger)
Monday, August 23rd, 2021 AT 12:06 PM