2004 Outback Wagon, 2.5, 4EAT, All weather package.
The headlights don't dim on my '04 when I hit the brakes. But I do notice the blower fan turns significantly slower when I apply the brakes. It also spins up a lot faster under acceleration. Also... try turning on your four ways at night while you have the door open. See if your dome lights get brighter and dimmer, in-sync with the four ways. Mine do. I've also noticed at idle sometimes when I have the dome lights on, the main dome will kind of strobe a little bit. If I rest my foot on the gas pedal and kick the idle up just a little bit, it stops.