Light comes on when braking
 

When I'm driving and I use my breaks this light comes on and I never noticed it until the other day. Is it normal or is there something wrong?
And I was driving my car in the video, and my speedo does not work lol


Video

I believe that is to tell you something's wrong with your tail lights.

What could be wrong with them

Good post, BTW. You made the prob perfectly clear.

Have somebody sit in the driver's seat and try your brakes, your reverse gear, your directional signals - and your headlights-plus-running-lights, front, sides and rear, all that with the engine running in neutral. You stand outside inspecting every light - sides, front and back - looking for bulbs that do not light or do not flash when they should. That's maybe what the computer is telling you. Something somewhere in that system ain't working right. If everything works, looks like a false alarm you can ignore. :( But I bet something ain't working.

There is a tail light doohickey(stop and tail light sensor)
 

IN the back of the car, behind the panel that hides the tail lights is a little rectangular box, they can vary in color, but I think they are all mostly the same, could be white or green. it could be bad or a corroded connection.
I have a few spares, not sure where they are exactly, but I do have some if you can't find a replacement, if thats the issue

a few picture
 

here is the white one I have, give you an idea what to look for

I put in JDM taillights and I throw the same light on the dash. All lights are working properly...