On a '92 the horn wire is a single Blue with a red stripe wire. It provides the negative back to the coil of the horn relay. So, touching this wire to any ground point blows the horn by energizing the horn relay.mattsmall said:i have an 87 supra and im trying to put a 92 steering wheel in and the 87 has 3 pins and the 92 has 4 pins plus the other 4 where the airbag is all i want is the horn to work so does anyone know what wires i splice and conect?