I bought a used 2000 Eclipse GS and I noticed that when the headlights are turned on, one bulb is dim and the other is bright and then when you switch to high-beams, the one that was bright becomes dim and the dim one goes bright. Anyone know what the problem here is?

there is no problem. this is how the eclipse head lights are setup. now if you have where both of the left bulbs on different head light units are bright when on low beams, and then both right bulbs on different head light units are bright when on high beams. then you have a backwards wired head light unit.

no.

Check the bulbs my guess is when one burnt out they used a lesser quality bulb.

well mine is like that. when my high beams are on my low beam lights are still on, they are just dim. and when my low beams are on my high beams are dim. and i have
5000 K light bulbs throughout my head light units. i spent $100 just for my light bulbs.

I agree. Replace all the bulbs at the same time, using the same brand bulb. While you're doing that, make sure your wiring harness for your headlights is fine and hasn't been damaged or melted.

must be common for eclipses.. mine was doing the same thing. deal said my connectors melted to my bulb.. wanted almost 200 to fix both sides.

Funny, I have the exact same problem. I tried to replace a blown bulb and the connector had melted to the bulb “tang”. I eventually changed both bulbs and now the high beam on my passenger side goes dim. The main beam works fine so I’m not that bothered at the moment. Someone had extended the wiring and replaced the connectors previously. I have to say the wires from the loom are pretty weedy!

I got my multimeter out and the earth is pretty good and the voltages are ok!

... This is not susposed to happen. It is not normal. It is a problem.

ok dude, i had the same problem with my 2001, all i did was replace the bulb, one of my three prongs to the plub was melted and thats all it was, there wasnt an equal amount of power going to all three prongs