I got the Mazda OEM rear fog light, but want to rewire it to work as a brake light. Does anyone know how to do it? Do I need to replace the bulb? Do I need a relay for the brake light to work properly? Do I just tap into the existing brake light wire? Any input is appreciated.

Thanks,

Sammy

 

I'd like to do this in the future, here's what little I know: the fog uses a 7440 bulb. If you want the fog light to operate the same as the 3rd brake light (only light when braking), then you can keep the same bulb.

If you want it to work like the tail lights (lit dimly when lights are on, lit brightly when brakes are applied) then you'll need to use a 7443 bulb (same size, dual filiment). I don't know about the socket though, it may need to be replaced or modified so that there are two contact instead of one.

Tapping into the existing brake light should work for either method.

 

thanks aipex8. i will probably just wire it to work the same way as the third brake light, just to keep it simple.