I got a phone call last night from my daughter who's away. She said the low beam headlights on her 99 Forester both went out at the same time. The high beams work fine. I asked her to try the fog lights with the stalk in low beam and she said they aren't working either.

 

Just so I'm prepared when she comes home this evening, is there a fuse for the low beams in the Forester that controls that entire circuit, as well as the relay for the fog lights? Or am I looking for something else?

Check fuses first. If the low beam fuses are blown check the connectors at the bulbs for melted terminals.

There are separate are relays for fog and head lamps, unless for some reason it has some kind of aftermarket wiring for the fog lights.

The low beam lamps and the fog lamp relay are grounded through the hi/lo dimmer switch. If the dimmer switch burns out it can cause this.

 

 

Possible other sources kinda depend on if it has Daytime Running Lights.

Thanks, Fairtax. The car is all stock, no aftermarket fogs or DRLs. I replaced the turn signal switch about (2) years ago when her turn signals quit working. I'll check fuses first and go from there.

The turn signal and dimmer switch are built into the same unit.

Was the replacement a new part or used? Aftermarket?

Replacement part was brand new. Standard brand, bought through RockAuto.

 

I'm out with the car now. All fuses are good under the hood. The relays in the underhood fuse block click when I turn the lights on. High beams work fine, still no low beams or fogs.

Ok. With headlight switch "on", I'm getting 12v at all (3) terminals on the headlight connector. When I switch to high beam, (2) stay at 12v and the other goes to 0v, as it should do with a ground switched system, correct? I checked the bulbs in my Impreza, and they're both good. Any ideas? Bad turn signal/dimmer switch?

Yep, you're on the right track.

Check for 12v on the low beam wire at the switch. Should be the same color as at the bulb connector.

 

Then check continuity to ground on the same wire. (key off)

Forester is fixed! The terminal on the dimmer switch for the low beams was melted. Got a new switch from my Subaru dealer this morning and got her back on the road.

 

Thanks again, Fairtax, for your help!

Awesome! Glad to help!

 

Note to self: signal switch = dealer part

Yes, I've been going to the dealer a lot more lately when I need special parts. I pay a little more, but they definitely seem to last longer.

I know this thread is older, but I am having the same problem on my 2008 Forester 2.5x.

I am curious, what is the “terminal on the dimmer switch” and where is it located?

Please and thanks!!!