Very few of them have a factory block heater in them I have owned 25 none with a blocker heater if it was one it would be in place of one of the freeze plugs you would see it right away
As far as the lighting problem goes ,looking at a wiring diagram I see they are controlled by a electronic control module .(LCM) - lighting control module . Checking power and grounds for the module and inputs from the main light switch would be a good place to start . Looking at a wiring diagram so you know which wires to test . Here is a web site for free wiring diagrams http://www.bbbind.com/free_tsb.html Enter vehicle info. Year , make , model and engine size. Under system click on lighting ,then under subsystem click on insturment panel lamps. Click the search button then the blue link.
Basic Electricity for Service Techs Ohm law Current Flow Opens ShortsHow to Use Multimeter to Troubleshoot Common ProblemsElectric Testing Techniques You Need to Know
Now looking at a wiring diagram for the power windows I see the LCM energizes the window regulator safety relay which powers the power windows , plus I see a left front door module . You may want to have a qualified repair shop with the right diagnostic tool to check for DTC'S - diagnostic trouble codes stored in the modules i mention . Probably save time and money . This may seam very complex but probably is somthing very simple ,a bad ground , corrosion , loose connection etc.... Knowing how to test electrical circuits is very important . Another problem is knowing where this componets are located in the vehicle . Buying a subscription to alldata would help . OE Info for Student and DIY er
The basics for a rough idle, check for a leak of some kind, fuel--egr--vacuum.
Use a gage and check proper fuel pressure. Also, see if pressure will hold for a bit with everything off. If it drops like a rock, you have a fuel pressure leak. Check the vac line on fuel pressure regulator, where applicable, if it has gas in it, the regulator is faulty.
Smell of your crankcase oil dipstick, does it smell like gas? If so, either you don't change oil and filter very often or there is a fuel leak getting into your oil.
Any applicable trouble codes?
Remove the outlet and inlet hoses from the heater core and hook up a hose to back flush the core through the outlet tube. The return outlet tube is usually the smaller hose.
Are you sure it's a code 52? I'm not seeing a 52 in the code index. Btw, code 12 is that the system passed it's automatic test. You could continue the chase to fix the air, but on a 20 year old car, it maybe a good idea to do an air suspension conversion on your Town Car and be done with it forever. The Best Lincoln Town Car Air Suspension Conversions 90 97