Check the electrical wires behind the dashboard, despite no problem for me, the electrical wires were worn by rubbing on the instrument clusters with the engine vibrations.
I'm still investigating but that area is a good starting point to look for a short that would cause fuses 7, 9, 10 to blow simultaneously. Obviously check wires to light switch and back to connector, particularly the solid blue wire which becomes live when headlamp selected. This same blue wire feeds via main loom to provide switched power to main/dip headlamp relay and and then loops back at relay with same colour wire to TSM so worth tracing both runs for shorts.
Richard
2018 Roadster 3.7 1966 Land Rover S2a 88 2024 Royal Enfield Guerrilla 450 1945 Guzzi Airone
