Drilled the end caps off
the aluminium part is a heat sink, which points towards a voltage transformer, take it off the plare and see whats inside![]()
I think you will find that this is wot yu had!
it is a high watt resistor - as already suggested - if it has gone open circuit - that why your lights didnt work. The anodised aluminium can wuth fins is designed to act as a heatsink - coz they get flippin 'ot!
1) to power the headlights in a dimmed (lower voltage) manner when the side lights where on (as already suggested)