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Test B: The Horn Is Always On

PINPOINT TEST B: THE HORN IS ALWAYS ON


B1-B2:






B2-B4:






B4-B8:






B9:






Normal Operation
The smart junction box (SJB) receives the horn signal through circuit 1 (DB) when the horn switch is pressed, which grounds through the speed control actuator via circuit 848 (DG/OG). The SJB then activates the horn relay through circuit 1323 (OG/RD). Voltage is sent to the horn through circuit 6 (YE/LG), and the ground is provided through circuit 1205 (BK).

Possible Causes
- circuit 1 (DB) short to ground
- circuit 6 (YE/LG) short to voltage
- circuit 1323 (OG/RD) short to ground
- horn switch
- clockspring
- horn relay
- SJB