What powers the little bulb is the same thing that powers all of the other hazard lamps, interior and exterior.

You push the green rocker. This closes two switches. The one switch gets battery voltage via the fuse panel. This now goes to the flasher relay which operates the relay and powers the hazard lights.

So in the relay there's yet another switch which is opening and closing. And when this switch is closed the path from there is to the turn signal switch, which is open, so on back to the hazard rocker where it's other, previously mentioned switch is closed which sends power to the switch lamp and the other lamps via the right and left sides of the open turn signal switch.

The lamps all have their own path to ground, hence the black wire.

It'll make sense if you look at the individual wiring diagram for the turn signal/hazard light system.


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'80 DL 2 door, '89 DL Wagon