I have a 1985 Toyota Cressida and the horn and glovebox light don't work (not sure if that's connected) I have tried changing the fuses under the bonnet, and got a new horn and light globe but still n
85 is an old car, and will have lamps out, a given
so replace it. the lamp.
the horn can fail many ways.
the horn fuse blown.
the horn relay bad.
the horn is bad.
we dont just gue$$ we use a tool called a voltmeter.
i put the meter across the horn terminals.
if just 1 , the meter goes there, an other lead to body ground
you mate, then honks
if the silent voltage goes to 12vdc, then the horn is bad. or
the base is rusted and is no good now. rust is and electrical insulator to a horn.
if no 12v, go to the relay,
i see the output of relay is dead, no 12vdc honkiing
i then check across the coil of said relay, coil, pins.
its 12v, that is a bad relay
its 0v, that is a bad horn switch
lets pretend the other relay contact pin is 0v. that is a blown horn fuse.
and guess what , fuse that look bad are, but ones that look good can be bad.
so my same meter, i flip the dial to RX1 ohms or low ohms
and read the fuse , and its infinity, dang, a hair line crack inside...
0 ohms is a good fuse.