Q: How can I troubleshoot and diagnose issues with a malfunctioning horn circuit?
A: If the horn doesn't work, check the Fuse, then disconnect the horn's electrical lead. Test the horn by connecting the lead to a 12V buzzer or lamp and pressing the horn control. If it doesn't complete the circuit, the horn is faulty. If the circuit remains open, replace the horn relay. If it's still open, check the harness wiring.