You have power supply problem to your fuse panel.the horns should be live all the time,the power comes back through the horn switch to earth.Try cleaning the horn contacts in the steering wheel with brakeclean or sprayon contact cleaner.
Are you getting power through the fuse?What you should do is replace all fuses ,don,t bother cleaning them.
Undo the screws holding the fuse panel in place and lower it down far enough to check the wires in the back. With a screw driver,check all the brass scews are tight.
With a multimeter,check that you have power comming through your new fuse,OK?,then the switch in the sliding control is faulty.OR the series resistor in the line to the fan motor has burned out.
you can access this by removing the radio and glove box.same story as the horn,use a cleaning spray to attempt to remove dust etc from the switch.Thats the top left slide.You should have power to your fan,
green/red wire #82 (lead number) motor speed 1
Green/yellow #83 "" " " 2
green yellow/black #84 " " " " 3
Black green/pink #86 Power,fuse 6
On the fan it'self,the colours are the same except that #85 is the earth and is the usual brown.
The plug for the slider is on the back left.
if no power to the motor end of that lead, then the switch will have to come out,that entails pulling the chrome bezel off,theres two nuts inside that you access via the radio slot.The bezel comes off and the complete slider mech. is then loose,you must undo all the cables by flicking off those high powered clips,watch your eyes![B)]Theres two screws on the back of the slider mech.(fire wall end of the car )
It is actually pretty unlikely that the motor has failed,I've seen lots of these and the mileage may have been high but the fans still worked .As for radio not working,there are no fuses near the actual radio,but if the radio is the original unit,make sure that you have power with ignition on,at the radio end.It's generaly a black plug with two pins.Theres no fuse on the panel,the feed comming direct from position "R" on the rear of the ignition switch,via A red wire with a green tracer.[