Confirm fuse F1.2, F2.38, F2.10, F2.4. Pay special attention to fuse F1.2 in the engine bay.
If no fuse problem found, confirm if +12 volts are present at the headlight DB/OG wire (switch off). Next turn the headlights on and test for +12 volts on the DB/OG and RD/YE wire. Post.
If no power at the headlight switch, check connector C134 located in the left hand fender well. Will be necessary to pull the fender liner to gain access.
If power on the headlight RD/YE wire, the problem is in the multi-function switch. Start with a double check of the connectors to/from the steering column.
As for the fan running, double check the connector to the PCM. Look for bent/pushed/dirty pins.
2003 GT Convertible (sold & missed)
2000 GT coupe (Craigslist project. Fixed. Now my DD). Windsor to Romeo swap.