Toyota Auris - 65 1800 air horn for toyota hybrid design 1.8 - carmalade
The canbus is a communication network system that runs at around 2.5 volts.It is not able to operate a consumer directly.The horn push is possibly on the network that switches a signal to a controller,which in turn will operate the horn.A car this new may have the later Flexray system installed.Inspection of any label on the horn should give its working voltage.