00 Continental Headlights/Turnsignals

This is a weird one!!! I have a 2000 Lincoln Continental, automatic, 2 wheel drive with 47,500 miles, that when I turn on the head lights they do not come on. I am able to click the brights on and they come on. When I turn on the headlights or the turn signals the interior lights light up like a disco pinball machine. The interior lights stop this and go off after I stop playing with the headlights & turn signals. :disappoin

I understand that the vehicle has a headlight/blinker module that may be the problem. I also understand that it maybe the headlight switch. I would like to know if I can test the module & switch, if possible because of the costs??
Has anyone ever heard of this before or do you know where I can begin to trouble shoot this? :banghead:

As always, thank you in advance for any replies!!
Oreo1

...Has anyone ever heard of this before or do you know where I can begin to trouble shoot this?...

99% of this type of problem, following closely to your description, leads to replacing the Multifunction Switch in the steering column. If the MFS is defective, testing it will require following power distribution using a wiring diagram. It's not simple. That's why most folks with this type of problem just swap the MFS with a known good one, it's easier (for most basic folks) than tracing wires.

Air Bag precautions need to be followed, a Factory service manual is recommended.

The MFS is making more headlines than the LCM (lighting control module).