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Test B: The Horn Is Always On

PINPOINT TEST B: THE HORN IS ALWAYS ON


B1-B3:






B3-B5:






B6:






Normal Operation
The smart junction box (SJB) supplies the switched and control voltage to the horn relay (part of the SJB). When the horn switch (part of the steering wheel) is pressed, the switch closes and ground is applied from the steering wheel switch harness through the clockspring to the horn relay through circuit SRH01 (YE/RD). The horn relay is then energized, applying voltage to the horn through circuit CRH02 (BU/WH), enabling the horn to sound.

Possible Causes
- Circuit CRH02 (BU/WH) short to voltage
- Circuit SRH01 (YE/RD) short to ground
- Steering wheel switch harness
- Clockspring
- Horn switch (part of the steering wheel)
- SJB