my 2004 coupe i bought with no bulbs installed (original owner was going to install new ones but died before doing) and his wife said the originals were ok but he wanted to upgrade to some other type and she cant find either the old working ones or the new ones, so i have read some threads and some say high beams tab up, and low beams tab down? i've bought a pair of OEM and want to install as hassle free as possible

 

well.....after some trial and error it finally worked out to bulb tab up for high beams, bulb tab down for low beams.... and trying to fit a bulb into a tiny fn hole and dealing with the retaining clip with fat fingers and short on patience im happy to say its worth it to drive at night !

 

Here's my guess on why one is up and one is down. We have projector headlights which basically means the instead of the light being spread evenly there is a point where the project cuts it off. This is so when you have your low beams on the light gets cut off before it would be shining in the eyes of oncoming traffic and is only displayed on "the bottom half". For high beams they opposite is true. You want the light to shine on the "top half" so that you can see further down the road.

My guess is that both projectors for high and low are the exact same part and one is just installed upside down from the other to cut manufacturing costs.

 

It might even be simpler than that, the H7 bulb has the filament almost down the centerline. Someone with a bulb out could confirm this but I suspect the tab aligns with the slightly off center side of the filament to give the high beam a little more "height" to extend down the road. Rotate the bulb 180 degrees and you will see the filament as a low beam.