* Fuse: This is the most common cause. Check your owner's manual for the horn fuse location and rating. A blown fuse will need replacing with one of the *same* rating.
* Relay: The horn often uses a relay to switch the higher current needed for the horn. The relay itself might be faulty, or the wiring to the relay could be damaged. Locating the horn relay in your Cavalier's underhood fuse box or inside the passenger compartment fuse panel will require checking your owner's manual.
* Wiring: Worn or damaged wiring between the steering wheel, the relay, and the horn itself is another possibility. A short in the wiring could blow the fuse repeatedly. Corrosion at connectors is also a common culprit. This requires visual inspection and possibly tracing the wiring.
* Horn itself: The horn could have simply failed. This is less likely than a fuse or relay problem, but possible.
* Steering Wheel Contact: The horn is typically activated by a contact in the steering wheel. Excessive wear or damage to this contact could prevent the circuit from closing. This is usually a more difficult issue to troubleshoot.
Troubleshooting Steps:
1. Check the fuse first: This is the easiest and quickest step.
2. Check the relay (if identified): Try swapping it with another relay of the same type (if possible and safe) to see if the problem follows the relay.
3. Inspect wiring: Look for any obvious damage, corrosion, or loose connections in the wiring leading to the horn and relay.
4. Test the horn directly (advanced): If you're comfortable with basic automotive electrical work, you could try bypassing the relay and wiring to test the horn directly with a 12V power source (be very careful!). This will help determine if the horn itself is faulty.
5. Consult a repair manual: A repair manual specific to your 1999 Chevrolet Cavalier will provide detailed diagrams and troubleshooting guides.
If you're not comfortable working with car electrical systems, it's best to take your Cavalier to a qualified mechanic for diagnosis and repair.
