Author Topic: Horn wiring?  (Read 4517 times)

rwh

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Horn wiring?
« on: July 10, 2015, 22:31:09 »
I am in the final stages of completing the restoration of my 230sl - built June 1964.  I need some detail on what happens at the steering wheel to activate the horn. My car has only one (driver's side) horn and there are two wires connected to it. I will be adding the other horn soon once I procure it.

What wires should I be looking for on the steering column that would activate the horn when the horn ring is depressed?  Where on the steering column do these wires exit?

Finally, for the passenger side horn, I believe other posts here indicate the wires pass from the engine compartment through a hole near where the air filter cannister sits.  Where do those wires connect in the engine compartment - what part of the harness? Are they routed along the back of the firewall?

Any help is appreciated.

66andBlue

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Re: Horn wiring?
« Reply #1 on: July 11, 2015, 00:16:24 »
What wires should I be looking for on the steering column that would activate the horn when the horn ring is depressed?  Where on the steering column do these wires exit?

When you press the horn ring it closes a round contact switch below in the steering column hub. See photo.
You would have to remove the copper-colored switch to see the wires, the positive is black-yellow-pink and is bundled together with the wires from the multi-function switch running down the column to a hand-shake connector. The negative wire is brown and connects to a ground terminal in the hub (I believe). For info on the multi-function switch look here: http://www.sl113.org/wiki/Electrical/SteeringColumnSwitch


Quote
Finally, for the passenger side horn, I believe other posts here indicate the wires pass from the engine compartment through a hole near where the air filter cannister sits.  Where do those wires connect in the engine compartment - what part of the harness? Are they routed along the back of the firewall?

The two wires for the horn on the passenger side come out of the harness where it runs from left to right across the front nose (under the black grill) to the right lamp bucket. The wires then go underneath the air filter and down through a grommet.
Alfred
1964 230SL manual 4-speed 568H signal red
1966 230SL automatic 334G light blue (sold)
1968 280SL automatic (now 904G midnight blue)

rwh

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Re: Horn wiring?
« Reply #2 on: July 13, 2015, 01:09:32 »
Thanks so much Alfred. That is exactly what I needed and the link helped quite a bit as well.
RWH