Not a headlight!

I’ve replaced the bulb, swapped bulbs, checked voltage, and the left low beam just doesn’t work. The right’s fine, the high beams on both sides are fine, and the fog lamps work. I just never get voltage at the left low beam. I used a multimeter at the back of the connector. Is it a relay? A fuse?

Oh, I wanted to add that the Haynes manual has a wiring diagram, but it’s pretty basic (standard) and doesn’t show the individual wire path through any extra switches, and is pretty disappointing when it comes to color description. Any other advice would be just miraculous. For what it’s worth, the car’s a 99 Galant, 2.4L 4 cylinder.

Read the wiring diagram. Then, check the ground wire. The low beam has it’s own ground, and the high beam grounds through the selector switch. If the light gets power, the ground must be good to complete the circuit. The light is getting power, because the high beam works. The high beam and low beam share the power source. So the problem must be the low beam ground.

I won’t lie, I’m an electrical novice. It’s a 9003 bulb, so it’s got 3 terminals. The top operates the low beam, where there’s no voltage on any setting, and the wire at the connector is orange with a blue stripe. The left side of the connector is a black wire, and the right is yellow with a red stripe, where there’s about 14 volts. Just to be sure I’m doing it right, I check with one terminal of my multimeter in the black, and the other in the circuit I’m testing? I’ll follow the orange/blue wire til it ends? Thanks so much, Knuckles. I’ll report back tomorrow.