The exterior turn signal lights all work normally and the right turn signal interior green arrow functions normally. When operating the left turn signal, the interior green arrow does not illuminate.

Any thoughts or suggestions? It is safe to operate the Crossfire with this problem, but my wife (who loves and drives this wonderful car) hopes there is a solution (and I am hoping there is an simple fix, but I doubt it).

 

Most likely the bulb. Does the side marker work?