Zener diode is still a kind of diode :fawk: Zener keeps power flowing one way until the current reaches a certain level then it allows it to go the other way!

And I have yet to see any automotive diagram with a mosfet (what the **** is that?), transformer, logic gate (WTF?), or rectifier. Rectifier sort of sounds familiar though, maybe logic gate does to.

But all the real complicated stuff is inside the computer. Mechanics don't fix computers, they just find out which one is broken and than replace it.