Honda 2004 Odyssey Service Manual page 1852

Circuit Diagram Horn Test/Replacement
1. Remove the front bumper (see page 20-128).
A
2. Disconnect the 1P connector (B), and remove the
horn (A).
3. Test the horn by connecting battery power to the
terminal (A) and grounding the bracket (B). The
horn should sound.
4. If it fails to sound, replace it.
B
B
A
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