Is there a difference between xenon vs bi-xenon headlights for the W203? Any information will be appreciated.

 

Pretty sure they just offered bi-xenons. When I got my C55, there was a lighting package. It added bi-xenons and headlight washers. I think it was the only upgrade from the standard halogens. It's possible earlier years had regular xenons with halogen high beams but I remember xenons with halogen brights only from my W202 C36. But it's been a while.

 

Xenons were available for MY2002, which uses frosty lenses. MY2003 they added bi-xenons which has the fish eye lens. The "bi" in bi-xenons means the HID bulb provides both low and high beams. In both xenon and bi-xenon configurations a halogen high beam is also used on top.

The ones on my car (see picture) are bi-xenons.