Before you throw a new std halogen bulb in you car, get out your red Owners manual and check the fuse diagram for the headlight in question. Stock Euro-type fuses are prone to build up a layer of oxide on them, stopping current flow at the most unfortunate times. If its not blown,take the fuse out & polish it against your Levis, then try it again. If this is the problem, it can be permaneltly fixed by replacing ALL the fuses with Busse 'GBC' type. These are US-made glass fuses with pointy metal ends to fit European cars and permanently stop the oxide failures.