Horn(s) Fail to Work. While trying to activate the horn, one or both horns fail to work. One or more of the following fault codes can be stored in the FEM: "8044A3 - Wiring, horn short circuit to earth" "8044A4 - Wiring, horn short circuit to positive" "8044A5 - Wiring, horn relay is defective or short circuit to positive" Water has entered the horn and caused it to fail internally (shorted out).