Low Beam Won;t work
If the high beam works and doesn't switch to the low beam then I would lean toward the switch in the column, most of them are pretty easy to change.
I second that, dy' It would be highly unlikely both low-beam bulbs burned out at the same time, I too would first investigate the switch on the steering column You may want to take a quick look under the hood to inspect the wires, unlikely but no harm in looking. My opinion only on my next suggestion---: no salvage yard switches. For one, if it does not work, even if the one you bought is bad, they wont take it back.
You have a Lincoln Town Car, but Ford just came out (in April 2014) with an extended warranty for headlights that don't work on the Mercury Grand Marquis. It is a 15 year/250,000 mile warranty and it is called Customer Satisfaction # 14N01. They will replace the LCM (Lighting Control Module for free. You could call the local Ford dealer to see if they have the same kind of extended warranty program for the LCM in the Lincoln Town Car LCM, or call Ford Motor Company. It's worth a try.
You'll never believe it but my solution to the no low beams was two new headlight bulbs !!!! I've never heard of two going out at the same time .
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