Below is a list of the Function keys and their assignments applicable to this model. F0. Lights on/off (if fitted on loco) F1. Sound on/off F2. Horn 1 – double tone F3. Horn 2 – double tone F4. Horn 3 – single tone F5. Buffer up F6. Coupling up to a train F7. Flange squeal F8. Guards whistle F9. Carriage door slam F10. Fan F11. Buffer clash on wagons F12. Compressor F13. Brake release F14. Acceleration/Brake override F15. Shunting mode/half speed F16. Aux 1