2001 Mercury sable

Sounds like the stalk/light and blinker switch on column may be bad or wiring going to it.

I have Mercury Sable Wagon 2001,my mechanic told me that some electrical issues (sounds like your headlights may be electrical) are tied to the ABS Automatic Braking System which in a car of this age may be completely shot. He hooked mine up to the machines and said the ABS was not even registering. I would ask your mechanic to check any fluids that relate to the electrical systems of your car. Mine flushed my brake fluid, which I guess you're supposed to do every 3 years.