so I hooked both up to the battery directly. The high tone horn started to squawk a bit, and with adjustment, let out its note. The low tone was silent, and no matter how much adjusting, wouldn't give a sound. But reading the links that James attached, I'm going to try to play with the low tone a little more before giving it up. BTW, they're not Lucas but replacements, so it isn't the end of the world to replace the low tone. In fact, I might buy me a pair of lucas off eBay just to prove to Keoke that I'm not cheap, just thrifty.