OK, now MAYBE I understand. I think those lights work off a different contact off the headlight switch. Best to consult a schematic for your particular model, then check for continuity at the pertinent switch contact. Also, the ground wiring sort of daisy-chains from one bulb socket to the next, try bringing one socket ground contact "down to earth" and see if the other bulbs light.

__________________
'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.