Technical description: Horn

Fig 1: Identifying Horn

Courtesy of SAAB-SCANIA OF AMERICA, INC.

Fig 2: Identifying Horn Wiring Diagram

Courtesy of SAAB-SCANIA OF AMERICA, INC.

The SID unit obtains information on the status of the horn switch from the steering wheel control.

Relay (68) for the horn is energized by the +30 circuit via fuse 3 in 342a. When the horn switch on the steering wheel is activated, the SID unit grounds pin 17, whereupon the relay operates and the horn is activated.

The horn is also used to acknowledge "TSL" locking of the car. The SID unit obtains information via the bus from TWICE to activate the horn.