Adam,

try swapping the two power wires to the bulb holder. There are 3 wires in
total, 1 ground, one to the running light (parking light) and one to the
turn signal.

Alistair

>The drivers side blinks rapidly and faintly.  Cleaned connectors in harness,
>no improvement.  Accidentally had my electrical pliers touch the 2 hot wires
>in the bulb holder at the same time, and bulb began to flash normally.
>
>What gives?  And should these yellow lights come on when I turn the
>headlights on? (they don't)