The low beam bulbs (H7) keep burning out on my sister's 2006 3s (2.3 5 speed Auto). I replaced them last fall, a month ago and then again yesterday. The bulbs are definitely burned out as the element inside is blown out. Of course I am careful not to touch the glass on the bulb during installation.

The terminal connections are a bit corroded and I'm thinking that may have something to do with it. I've tried my best to clean out the terminal connectors but the female end on the harness is difficult since you can't just use a piece of sand paper or a wire brush. Does anyone know of a good tool/method for cleaning those out?

Also, after searching the forums it looks like some other folks are experiencing this issue as well. Anyone know if someone has gotten to the bottom of this and determined if the cause is terminal connector corrosion or something else?

Another thing is the way Mazda designed the mechanism that holds the bulb in place is quite springy and allows the bulb to bounce around a bit if the vehicle experiences a bump in the road.