One problem related to horn assembly has been reported for the 2005 Volvo S40. The most recently reported issues are listed below.
The contact owns a 2005 Volvo S40. The contact stated that while driving at 55 mph, the steering wheel and entire vehicle began to shake as there was an abnormal noise. In addition, the air conditioner, radio, horn and sun roof failed to function when activated. The srs warning light illuminated. The vehicle was taken to an independent mechanic who diagnosed that the ecm, front axles and struts needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 194,000.