My '91 Civic wagon's horn doesn't work.  I tried to fix it by replacing the
fuse.  The new fuse blew immediately. So I traced the wiring and found
corroded and broken wiring at the horn.  I fixed the wires but the fuse
still blew.  I took the steering wheel off to see if there was something in
the horn switch.  This car is old and there is nothing electronic at the
steering wheel except the horn (i.e. no airbag, no cruise control, etc.).  
I touched the copper clockspring to the metal steering wheel hub thinking
this would "complete the circuit" and would either sound the horn or blow
the horn fuse again.  But instead I heard a some beeping from within the
car, not the horn, but more like a warning beep, like when the lights are
left on or something.  Then the car wouldn't start, and there seemed to be
no power (no radio, etc.)  However, when I turn the key off, there is a
fast loud clicking coming from some sort of device located near the floor
in the center of the car, very close to the heater vent.  When I turn the
key back on, the noise stops, but car remains dead.  Any ideas?