My headlights don’t work
I see the “My headlights don’t work” question on auto forums every day. The forum posts always leave out critical information like year, make, model, as if every vehicle is wired the same way. I encourage you to click on the wiring diagram jpg below to open up a PDF of wiring diagrams. I show three ways carmaker use to control headlights. But there are at least six other ways to do it. So if your headlights don’t work, whether the brake lights don’t come on, brake lights won’t turn off, headlights don’t come on, headlights don’t shut off, or any other issue where something switched doesn’t work properly, at least be smart enough to provide the vehicle information in your question.
It is simply IMPOSSIBLE to answer your question without that information. Anybody who does, it just throwing outdated information your way that may cause you to chase your tail in a fruitless effort to solve the problem.
©, 2015 Rick Muscoplat