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Horn Relay Circuit

  1. Locate horn relay wire connectors marked "X" and "Y" on wiring diagram illustration. Use a voltmeter to measure for battery voltage on the male side of connector "X" at blue/yellow wire. Use a voltmeter to check for battery voltage on the female side of connector "Y" at blue/yellow wire. With voltmeter still connected to "Y" connector female lead, depress horn switch and voltmeter should read zero.
  2. If preceding checks are satisfactory, connect voltmeter to yellow/green wire at horn relay and ground. Depress horn switch and voltmeter should read 12 volts and horn should operate. If horn does not operate, check circuitry between relay and horn.