Current draw for a horn while operating should be 4.5-5.5 amperes at 11.5-12.5 volts. High current (more than 20 amperes) indicates an overhead horn winding or short. If this condition exists, replace the horn. A current reading of approximately 18 amperes usually indicates that the horn contact points are not opening. If this condition exists, the horn current requires adjustment.

No current reading indicates one of the following conditions:

If the wiring is good, the horn current will require adjustment. Perform the following steps in order to adjust the horn current:

1. Turn the adjusting screw clockwise in increments of 1/4 turn in order to increase the current.
2. Turn the adjusting screw counter-clockwise in increments of 1/4 turn in order to decrease the current.