The rear fog lamp operation is possible with the headlamp switch in the HEAD position. With the headlamp switch in the HEAD position, voltage applies through the closed contacts of the headlamp switch to the rear fog lamp switch and to the rear fog lamp relay. With the rear fog lamp switch in the ON position, a ground path completes through circuit 1977 to the rear fog lamp switch and through circuit 150 to ground G201. This closes the contacts in the rear fog lamp relay and current flows to the rear fog lamp which grounds through circuit 250 to G401.