The awnser is in the question, yes, your headlights grounded, yes, there power comes from a fuse link. when you start a car energy flows from the battery to start seleniod and at least 2-3 fuse links are there one for electronics and one for lights if one blows plan on spending 100$ to fix it at a shop
It is likely that you have lost a master fuse or fusible link. The headlights are nearly always powered directly from the battery through a fusible link or large, under hood fuse.
It is already grounded through the faucet and water pipes. Even if the supply lines are PVC, it will still be grounded through the water.
through the tires
I just had the same problem in my '97 Nissan pickup. Both headlights stopped working at the same time. I went through some hoops, including trying a new headlight switch, but it turned out to be some corrosion in the plug for the fusible link that bolts onto the positive terminal of the battery. I cleaned that out and it is working fine again.
your headlights will burn out faster and could possibly blow a fuse, but you would go through headlights and a drastically increased rate if you use headlights when they are unneeded.
The fusible links on a 1993 Ford Ranger are located throughout the vehicle and primarily in the engine compartment. They prevent circuit overloads and must be replaced each time they are burned through.
You are electrocuted but only happens if you are grounded
the light doesnt go through the fog
A transformer doesn't 'conduct current through the ground'. However, in the event of a ground fault in the circuit supplied by a grounded transformer, the resulting fault current will flow through the earth back to the grounded terminal of that transformer's secondary winding.
there is no ground wire it is grounded through the case
Of course it can.
Grounded for Life - 2001 I'm Looking Through You - 5.7 was released on: USA: 5 November 2004 Germany: 27 October 2007 Hungary: 29 April 2011