Re: Horn Relay

Posted by Alex Billson on January 19, 1998 at 16:53:02

In Reply to: Horn Relay
posted by Paul Reasenberg on January 19, 1998 at 15:22:42

Paul, I am not a purist just for the sake of it but I hope I'm a little practical. My car had a little modern crud on her when I bought her and I pulled a relay out of the horn circuit
for the following reasons:
1. Henry generally knew bloody well what he was doing and the original system worked/works for a lota people.
2. The system works fine if you take out the light switch assembly at the bottom of the steering column by unclipping the lighting switch and cleaning the gunge off the central wire
Consider putting a modified steering box end plate (that is one with 6" of tube) on the steering box if one is not already fitted as this will protect yout light switch too.
3.You not only have to mount the relay but when you do you introduce a whole new set of contacts and its coil to go wrong. Remember the acronymKISS standing for Keep It Simple Stupid. (not an insult just good advice generally).
4. If your wiring is affecting the horn that badly it probably should be the primary cause of your attention.
Have you got a really good earth from the battery to the frame? Remember the steering box has to have an earth return back to the battery. Paying attention to a good battery earth might improve your lights as well as starting too!
Disconect the battery and beg or borrow an ohm meter and measure each of your wires to find the culprit. Be sure to measure resistance from the steering column wire to earth with the button pushed down. It should be just about a short circuit.
Generally the horn wire in the steering column either works, blows the horn all the time (or intermittently), or doesn't allow the horn to work at all. A relay can help patch up a high resistance wire here but I wouldn't have one, I'd replace the wire.

Its better to cure a problem than "repair" around it. I dare say that the biggest threat to our model As is the well meaning "improvements" that are added to our cars over time.

Whatever you do Good luck
Alex

: I hope this doesn't offend any of the purists who read this board, but I am considering a modification of original design. Another A'er once suggested installing a 6V horn relay to avoid the sometimes poor electrical contact the horn button may make, as well as the resistance of the wire to it. Indeed, an old automotive horn relay I obtained and hooked up with clip leads brings new Aoogah power to my horn. But...I notice that the relay, which is a 3-contact unit, would need to be mounted on an insulator, because the horn button is a grounding switch. Has anyone gone this route?
: Paul

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