Test B: The Horn Is Always On

PINPOINT TEST B: THE HORN IS ALWAYS ON

B1-B2:

B2-B4:

B4-B7:

B8:

Normal Operation
The smart junction box (SJB) receives the horn signal through circuit 1 (DB) when the horn switch (part of the steering wheel and the driver air bag module) 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). The SJB also provides a momentary ground for the alarm chirp and an on then off again ground if an intrusion is detected in the alarm system.

Possible Causes
- Circuit 1 (DB) short to ground
- Circuit 6 (YE/LG) short to voltage
- Circuit 1323 (OG/RD) short to ground
- Horn relay
- Clockspring
- Horn switch (part of the steering wheel and the driver air bag module)
- SJB