Do you toot-toot
too much?
No,
I am not talking about flatulence; that’s a problem for you to talk over with
your doctor. But if your problem is that the horns on your old car seem to have
a mind of their own and toot at unwanted or embarrassing times, or don’t toot
when you want them to, we may have a solution for you.
We
talked in an earlier article about restoring and tuning your tooters. The horns
themselves don’t decide when to honk. That is the function of the horns, the
horn relay, the horn button and the nut behind the wheel. The horn relay
supplies the electric current from the battery to the horns. The horn button
controls the horn relay and, of course, the nut behind the wheel decides when
to push the horn button or ring.
Because
the horns require a lot of amperage, heavier wires are needed to supply ample
electricity to the horns themselves. The relay acts as a heavy wire connector
directly from the battery to the horns. The relay consists of a low-amperage
electromagnet that closes a set of high-amperage points, allowing the direct
connection from the battery to the horns. All the horn button does is provide a ground that activates the relay.
If
the small wire going down through the steering column grounds anywhere, the
relay closes and the horn honks. On the other hand, no ground,
no toot. This wire and its terminal at the top of the column must be well
insulated against grounding except when the horn button or ring is depressed.
The
horn button is usually held away from grounding by a cone-shaped spiral spring.
If this spring breaks or gets weak, the horn will tend to toot on its own. If
you need to replace this spring and can’t find one, here is a little hint. Find
an old flashlight that has the same shape of spring. If it doesn’t fit exactly,
you can usually bend it into the right shape.
There
should also be some foam rubber insulation that keeps the mechanism from
shorting out and also holds up the horn ring, if so equipped. This rubber tends
to rot and fall apart. You can always find some foam rubber stock and cut a new
one. Sometimes it will take more than one thickness to insulate properly.
Don’t
forget the small insulating ring between the top wire terminal and the steering
post. If this is broken, you may be able to slip a rubber O-ring (or two) over
this terminal. If you are replacing the wire going down the steering column,
you can use heat-shrink tube to make sure the top terminal is insulated from
the steering column post. You can use a continuity test light to make sure you
are getting a ground when the button or ring is depressed.
Next
you will want to check the wire from the bottom of the steering column to the
horn relay. A short here can cause a toot when you don’t want it, or, if broken
somewhere, no toot.
Assuming
that your horn button is working well, we now have to look at the horn relay.
This is normally on the firewall in the engine compartment. It is a small black
box that is sealed, and has one or two mounting screws and three wires
connected to it. If you can tap this and the horn blows, it means the relay is
defective and needs to be replaced.
As
a matter of fact, if you have the slightest concern about this relay, replace
it. They are quite inexpensive and readily available at most auto parts stores.
Just be sure you get the right voltage. The three terminals are generally
marked “H” for horn, “B” or “P” for battery or power, and “S” for switch. The
battery connection is usually the center post.
If
you are ever out on the road and your horn starts honking on its own, you can
disconnect the battery terminal or the horn relay and do your repairs when you
get home.
Well,
there you are with good working horns again, but, if you are out driving and
the horn accidentally toots when you pass a good-looking girl in a tight green
sweater, you can tell your wife that it must be the horn relay acting up again.
My own experience tells me that will only work once or twice at the most.
See
ya later,
—Walt