My friend was driving behind me earlier today at night, and when we got out of the car, he told me that my brake lights were blinking funny. Basically, when I have my headlights on, the dim brake lights would start blinking (one side would turn off for half a second while the other side would get brighter + third brake light would turn on). This problem only occurs when the engine is on - no problems with lights at all if engine isn't running. Brake lights are bright with no problems when brake pedals are pressed.

Here are the "mods" I've made that could contribute to this issue:
90/100W Headlights
LED parking lights
7W CREE Brake lights
LED license plate lights (same as parking lights except white)

Something else I've noticed is that pressing the brakes also turns on my parking lights.

I don't know what's happening, especially since this problem only happens when the engine is on. Any help is appreciated.

 

If you did not mess with wiring for any of these or anything else just try putting stock bulbs back in one at a time.

Those bulbs in the taillights are not very good as only shine straight back and will not light up the tail lens very well. Best to just find some stock type with higher output and avoid LED.