The electrical system of the Aermacchi Harley-Davidson MSR-100 Baja from 1972, with lights, drawn circuit by circuit. Each wire is labelled with its colour.
Always check a wire with a multimeter before you connect it, and disconnect the battery first.
Circuit 1IgnitionThe black wire goes through the terminal block to the coil. The brown wire goes from the coil to the handlebar switch. The left coil terminal is earthed.
Circuit 2LightingThe red wire feeds the handlebar switch. It sends the current to the headlamp through white or black.
Circuit 3Tail light and clocksThe yellow wire feeds the tail light through the terminal block. The third tail light wire goes to earth at the coil.
Circuit 4Stop lightThe green wire feeds the stop light through two terminal blocks. The same wire goes to the stop light switch.
Read this firstWatch out forUncertain colours and terminals
- The inside of the handlebar switch is not shown in this diagram. Check with a meter which terminals are connected in each position.
- The book does not say which wire is high and which is low beam. Where this page does say so, it was worked out from the warning lamp. Check it at the headlamp.
- The Baja without lights has its own page.
- The handlebar switch has its own earth wire.
- The green wire to the stop light switch runs through a connector. The other side of that switch is not shown in the diagram.
Our own drawings per circuit. The connections are based on the workshop manual for this model. Not an official publication of the manufacturer.