Hello - Here's what my wife wants me to do:

She wants a larger horn for the smart car. So, she found this small air horn. Looks easy enough to install, however it operates with a 30A relay. Two questions:

1) Is there somewhere safe on this car to wire this up?
2) If no to the above, would it be acceptable to install it directly to the battery (fused of course); does the smart car electrical system have enough "overage" to power aux. items like this?

Thanks - Alan

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Don't know if it's too late to return the other horn but a lot of owners have installed this one: http://www.wolo-mfg.com/air.htm

No relay required - plug and play. Any horn installation will require some panel removal. smart also sells their own horn upgrade kit: http://www.evilution.co.uk/index.php?id=191

More info on horn install: http://www.smartcarofamerica.com/forums/f75/tutorial-replacing-fact...
With regards to those horns from wolo - that is almost exactly what I have (slightly different packaging, but I would bet all of the parts are from teh same factory overseas).

So, then, I guess installing a 30A horn instead of the original smart horn is acceptable? Anyone know this for sure? Thanks
Thanks for your help -

I just purchased a 12V horn from Griot's Garage that other people have installed with minimal effort (just removing the panels and a couple bolts) no compressors, hoses, etc.
Great! Same one I have, just have to get it on the car.
So, is this your understanding of the Griots Garage Horn install:

1) Remove appropriate panels
2) Remove existing horn
3) Install new horn (mechanically, and by attaching two+ wires)?
4) Re-Install panels.

No relays, additional wiring, etc?
That is correct (even though I haven't done the install, plenty of others have.) The stock electrical plug even fits the connector on the new horn - it is truly plug and play. Just need to ensure the opening on the new horn is facing down.
I installed a Wolo bad boy last week. No relay necessary. The instructions indicate that the enclosed relay is for motorcycles. Great horn!
You can also install the Wolo Bad Boy horn through the driver's side wheel well. If you turn the wheel all the way to the left, you can reach the 3 plastic fasteners that hold the liner in place. Remove them and you can bend the liner and slide in the new horn in through there. After you take off the factory horn, you connect the original wires to the new horn and mount the Wolo on the other side of the bracket (closer to the firewall). It's a tight space to work in, but I was able to do it in under an hour in 30 degree weather. (I mention the temp, just in case anyone was wondering about the flexibility of the wheel well plastic liner.) There are also good DIY threads on the SCOA forum.
Since I just bought my second air horn from Griots garage.....

Does anyone know if there is any difference between the wolo and the griots? They look about the same, and it appears they have the same amperage....The Griots appears to be a 12v 10a

My problem is I know more about 3 phase electrical than i do 12v electrical, and I don't want to screw up my wife's car.
Alan, they are essentially the same horn. Connect up the factory plug and you're good to go. Here's a link to a photo from Clicker of his installed:

I would imagine hooking this directly to the battary would work, especially if you had the 2.0 upgrade. I have to use a portable oxygen compressor for my wife and plug it directly into the 12volt outlet, works great. make sure u put an inline fuse
David Owen
you don't need to take the car apart.. don't need to even take the old horn off... just open the front "hood" panel, and look into where the OEM horn is, unplug the wire harness to it and pull it gently up into the light of day. There, you can test your AIR horn's polarity with the wire harness cables.... Now that you had someone honk the air horn that was in your hands... and scared yourself half to death, put it in a nook under the "hood" and affix it with zip ties. "DONE!"

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