Dear Car Talk:
The poor lady was in tears. The loud horn would not stop. She tried to remove the battery to her key remote, with no luck. We opened the hood, and I removed one battery wire, and it stopped. At least I bought her some time, but how do you really stop the darned horn? I'm a bricklayer, not a mechanic. But I felt like a knight in shining armor for just a minute, as she wiped away a tear. Still, I'd love to know the answer. -- Svend
I assume you two are dating now, Svend. But if you want to take the relationship to the next step, you will have to come up with a more permanent solution.
We know it's not the horn itself. The horn is clearly working. So it's likely to be either the horn relay or the horn contacts.
Start by checking the relay. You'll find a box of relays under the hood. If they're not labeled, you can just start pulling them out, one at a time, until the horn stops blowing.
Often, there are several identical relays in that power-distribution box. So if you can find another one with the same plug-in pin configuration, swap the two of them. If the horn stays off, you've diagnosed the problem. Of course, now her windshield wipers will be on all the time, so you'll still have to get a replacement relay in order to complete the repair.
If, on the other hand, the horn starts up again when you plug in an identical relay, then the problem probably is with the horn contacts, which are located in the horn pad -- right in the middle of the steering wheel.
That's not something you're going to fix yourself. The air bag is in there, and if you think dropping a brick on your big toe hurts, Svend, wait 'til you set off an air bag 4 inches from your face.
So if the mechanic removes the horn pad and the horn stops blowing, then obviously the problem is in the pad. And perhaps replacing it is in order.
If the horn doesn't stop when the horn pad is removed, then you could have a short further down the line. At that point, you'll need to Google the wiring diagram for the car.
But getting at least as far as the horn pad ought to get you to the point where she'll introduce you to her parents, Svend. And then you can bring that wiring diagram to discuss with them over dinner.