Since you've already checked the fuses and confirmed the horn works when wired directly, the problem is almost certainly with the relay itself or its wiring.
Here's a systematic approach to finding it:
1. Consult a Repair Manual: A Haynes or Chilton repair manual specific to your 2006 Chevy Aveo is your best bet. These manuals usually have detailed diagrams showing the location of all relays and fuses.
2. Look in Common Relay Locations: Relays are often found in one of these areas:
* Under the hood: In a fuse box or relay box, usually near the battery. This is the most likely location.
* Inside the passenger compartment: Sometimes under the dashboard, near the steering column, or in a fuse box inside the car. This is less common for horn relays.
3. Check the Fuse Box Diagrams: Even if you don't have a repair manual, the fuse box (both under the hood and inside, if applicable) usually has a diagram on its cover. This diagram may show the location of the horn relay, even if it's not labeled as such (it might be listed by a number or a circuit description).
4. Trace the Horn Wiring: This is more advanced, but you can try tracing the wires from the horn itself. Follow the wires back; you should eventually find them connecting to the relay. Be careful not to damage any wires during this process.
5. Online Forums: Search online forums dedicated to Chevy Aveos (like on car-specific websites or general automotive forums). Someone may have had the same problem and posted a picture or detailed description of their relay location.
Important Considerations:
* Multiple Relays: There might not be a single "horn relay." The horn circuit might be controlled by a larger module, and the horn's function is part of a more complex system. This is less likely but possible.
* Grounding Issues: While you've tested the horn directly, a poor ground connection could still be preventing it from working through the normal circuit. Check the horn's ground connection for corrosion or looseness.
If you can't find the relay after trying these steps, it's best to take your Aveo to a qualified mechanic for diagnosis and repair. They have the experience and tools to quickly pinpoint the problem.
