Fan does not switch off

not really sure what your problem is, heater fans usually do stop running when ignition is off

Some fans do keep running after engine is switched off for a short period of time (up to 5 minutes) Check with a service person (ford) to see if that is the case or if you have a faulty sensor.

The fan runs for a short time, after ignition off, to continue to cool the hot engine.

Hope this helps your out. I know the diagram and locator is a bit blurry but hopefully it gets what you need.
Drivers kick panel:
Front wiper 20A - Front wiper system Cigar 15A- Cigarette lighter Audio 10A- Audio, remote control mirror Air Bag 10A -Air bag diagnostics Stop lights- 15A -Rear brake light, high mounted stop light ECU B+ 10A - Shift lock actuator, transaxle controle module, radio, engine control module Room 10A - Interior light, clock, ignition key reminder, rear cargo area light switch ABS 10A- Anti lock brake system control unit ECU IG1 10A - Transaxle control module, shift lock actuator, ABS control unit, DRL unit Meter 10A - Instrument panel, back-up switch, electronics time control module, inhibit switch Turn signal 10A- Hazard switch ,front and rear turn lights, turn indicator IGN1 20A - Ignition switch ABS 30A- ABS pump motor TNS 30A- Tail light, license plate light COOL/FAN 30A- Cooling fan Cond/Fan 20A- A/C condenser fan Starter 15A- Start signal , Fuel pump Blower 25A- Blower Motor SR/ACC 10A - Ignition switch Hazard 15A - Hazard and turn signal light D/Lock 25A- Door locks ABS 30A - Anti lock brake system control P/W RH 20A- Power window motor right hand P/W LH 20A- Power window motor left hand IGN2 25A- Ignition Switch
Engine compartment :
Head 25A- headlights IG 2 30A- Ignition switch IG coil 15A -Ignition coil, condenser,generator IC regulator, diagnostic connector. O2 down 10A- Rear O2 sensor O2 up 10A- Front O2 sensor Fuel pump 10A -Fuel pump unit Injector 10A -Fuel injector ,camshaft positioning sensor, purge solenoid valve, EVAP, IAC actuator, Mass Airflow sensor, EGR stepper motor. fuel pump relay coil, vehicle speed sensor. A/Con 10A - A/C compressor controls, cooling fan BTN 30A- Brake light , high mounted stop light. Tail light LH 10A- License plate light, tail light , rear combo light, instrument panel illumination Tail light RH 10A-License plate light, tail light , rear combo light, instrument panel illumination Head low 15A- Headlight Head Hi 15A-Headlight Horn 15A- Horn

Inside kick panel

Switch needs replaced in dash. you will have to take it out of the car and put a new fan switch, should work in all positions, and since its stuck that would be what I would replace first, not sure on procedure. http://hyundaisonata.com

Regulator

The fan motor is bad need to be replaced

should turn off after time, because of the age im not sure if it has a rad fan switch on side of rad, if so its that, unplug and it will stop, replace it, bear in mind it can stay on for upto 3 minutes after a journey, you can increase the temp to stop this coming on so early.
if no rad switch on newer they suffer a bad etc, please note your colour when ordering.

with a forced draught burner the fan motor would be checked via a pressure switch. if the pressure switch is not set correctly or the fan is too weak the contacts will not be made in the switch and the burner will lockout. if the damper is not open enough when the fan runs then the air supply will be too small for the switch to make. check to see if you have a capacitor on the fan windings if this is faulty then the fan will fail intermittently.