Hiroller

The best thing to do is check for 12VDC at the input to the light when the peddle is pushed. If you don't get power you won't get lights. If the power is there, you have a bad bulb, socket, or ground. If no power is available at this point, then move back to the brake light switch and test. You should have power on one side all the time, and on the other side only when the peddle is pushed. If no power on either side, move back to the brake light fuse and check for 12VDC on both sides of the fuse. This will check the fuse at the same time you take the readings. If there is no power at this point, move back toward the battery in the circuit. When you find the point where you have power, you will know the problem is between that point and the previously tested point with no power. I think you get the idea.

As for the LED lights, check to be sure you didn't wire them backwards. LEDs are polarized. They have a positive and a negative unlike a light bulb. Individual LEDs also require a resister on the positive lead. I'm not sure what your LED strip does or does not need. Check with the manufacturer to be sure they are for use in a 12 VDC circuit or if they require a resister in series.