Where can you find an electric diagram to repair the horn on a 1989 Ford Aerostar?

Answer 1

Well, I'm not sure there IS a readily-available electrical schematic for so simple a device as the horn. In my Aerostar, as in most vehicles, the horn is powered by a single wire from the + terminal of the battery (so it will work even when the car is off) through the horn switch in the steering wheel. The circuit is grounded from inside the horn to where it bolts to the car without additional wiring. The + wire goes to a coil inside the horn, like that inside a solenoid. This coil drives a metal bar attached to a bladder that sucks air in and forces it back out of a shaped chamber on the other side of the bladder from the bar. When current is applied, the solenoid pushes the bar in and out of a cavity through the coil at high speed, causing the sound you will hear. That's my best answer to your question. Now for some input you may find helpful: 1. Most horns are disposable devices, in that they are machined together at some point in the manufacturing process such that they cannot be disassembled without incurring permanent damage to the device. This makes attempted disassembly dangerous due to the unlikelihood of most people having the very specific industrial tools that would be needed to take some thing like this apart without damaging it bolted to the floor of their garages. Because of this, hand tools or even power tools are used, often by inexperienced people who are un-familiar with proper tool use guidelines, and so personal injury is frequently the only result. 2. Further, in my experience, the simple devices like horns, solenoids, relays, etc. which wear out over time do so not because of an electrical failure, but a mechanical one. Try this: get a multimeter with a continuity check function, or a nine-volt battery, some wire and tape, and a small light bulb or L.E.D. Or you can just use your tounge. But once you have these, check the connection from the post to anywhere on the housing. There should be some resistance from the driving coil, but otherwise the light should come on. If so, then you have either a stuck bar, a cracked or disintegrated bladder, or a split coil housing. Also, the insulator washer that seats on the post to insulate it from the housing may be cracked, worn, or completely gone. This condition would cause a consistent short resulting in a blown fuse. (While you're at it, check the fuses) If not, then it really is an electrical issue )probably(. Either way, I guess my point is that unless you are using this horn for some other purpose than being a car horn, and you don't otherwise need THIS specific part to work, I recommend taking a walk to a parts store and getting a new one--they're like five bucks.