So I have the interior light in my beetle and it hasnt been working.

I recently bought a new interior light housing and bulb from Mick motors, however it only has 2 terminals where as my beetle has 3 wires, 1 yellow one and 2 white ones ( i dont know if the previous owners put in custom ones)

Any ideas how to get it working?

Yeah the new ones dont have the 2 settings. one setting is for on and another is for on when doors are open. So put the yellow wire on 1 end then put one of the white ones on the other and turn the light switch on and see what white wire you will want to use (one will be the earth and the other is only earthed when the doors are open. hope this helps. from dylan

the usual setting is 3 wires but don't worry one wire will be power that is permintly on the other is earth from the door or the on switch