The Ford Barn - View Single Post

rotorwrench · 06-20-2021, 12:29 PM

A transorb or varistor can be attached across the horn relay control terminals to prevent transient voltages but it may be the back flow from the horn vibrator coils causing a higher return voltage. It could be much more than 6-volts. In this case a capacitor should be installed in the horn vibrator circuit. Ford did this in the 30s but quit using them after the horn relay became the normal way to control the circuit.

The horn has about the highest current draw with exception to the starter so it can put out a pretty good transient voltage into the car frame & body. That an a sweaty arm on the window sill will get your attention pretty quick.

06-20-2021, 12:29 PM	#7
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,462	Re: Shocked by the Horn!!!! A transorb or varistor can be attached across the horn relay control terminals to prevent transient voltages but it may be the back flow from the horn vibrator coils causing a higher return voltage. It could be much more than 6-volts. In this case a capacitor should be installed in the horn vibrator circuit. Ford did this in the 30s but quit using them after the horn relay became the normal way to control the circuit. The horn has about the highest current draw with exception to the starter so it can put out a pretty good transient voltage into the car frame & body. That an a sweaty arm on the window sill will get your attention pretty quick.