Headlights are crabby

[toyota>subaru]

Hey I bought a legacy gt that had hit a deer in the front passenger over a year ago. When I bought it the driver headlight was nice and bright and the passenger was a dull p.o.s. and when I turned the brights the driver got brighter but the pass. got dimmer. I messed around with the wires on the pass. side till both headlights were bright and then soldered them up in that particular configuration. However, with this setup my brights weren't working and the brights dash indicator was half lit up at all times. Drove like that for nearly a year and a month ago I noticed the dash bright indicator wasn't lit up so I flicked the brights on and they both appeared to work. Well... now my indicator comes on intermittently and the pass. light will not work on dim. I tried new bulbs but the driver is still the only one that lights up. If I turn on the brights both work.

Just getting a little fed up with it and I never got to see how the wires were connected originally because the plug got ripped off in the deer incident. Also if it helps any.. on accessory the fans will turn on and go from low to high and back to low over and over. Any ideas? I know I have seen a number of cars with the ridiculous dim and bright headlight malfunction rolling around.

[chuckthefuk]

What year Legacy?

Usually its 2 ground switches and 1 constant power.. If its a 2000+ the passenger side headlight connector uses extremly thin wires..

Give us more info.
-Chuck

[toyota>subaru]

What year Legacy?

Usually its 2 ground switches and 1 constant power.. If its a 2000+ the passenger side headlight connector uses extremly thin wires..

Give us more info.
-Chuck

Its a 97 GT. Has the 3 prong plug on it. The fuses are good and as far as I know the relays are good.

[chuckthefuk]

Good you have the simple connectors.. They changed in 98 to a different style

https://sl-i.net/FORUM/images/imported/2007/04/jdmprojector01-1.jpg

https://sl-i.net/FORUM/images/imported/2007/04/jdmprojector02-1.jpg

-Chuck

[toyota>subaru]

ok cool thanks. I have a different plug from what I can tell but I just followed how the wires were routed on your passenger side. I soldered it up and just finished. Now when my dims are on they both appear to have the same brightness. When I flip on the brights the driver gets brighter as usual but.. the passenger gets dimmer. As the passenger gets dimmer it looks like it gets real dim at first and then slowly regains some brightness. Its awfully weird. Also which filament is the bright filament? The one closer to the plug of the bulb or the one with the little reflector around it that is farther towards the end of the glass? By the way thanks for the help.

[chuckthefuk]

The driver side light will always be brighter then the passenger since the wiring is shorter.

And what exactly are you talking about you should have 2 bulbs. Both should be dual filiment. Turn signal and Hi/Low beams..

Both the hi/low are used in the same reflector housing it just gets brighter when you hit the hi beams.

Sounds like your bulbs are wonky switch them out with some cheap-o's and compare.

=Chuck

[toyota>subaru]

The driver side light will always be brighter then the passenger since the wiring is shorter.

And what exactly are you talking about you should have 2 bulbs. Both should be dual filiment. Turn signal and Hi/Low beams..

Both the hi/low are used in the same reflector housing it just gets brighter when you hit the hi beams.

Sounds like your bulbs are wonky switch them out with some cheap-o's and compare.

=Chuck

alright I understand I have two bulbs and that each are dual filament. Forget about the turn signal. Now from what you say a single (dual filament light bulb) uses both filaments during high and low beams. I didn't know that. I was just trying to figure out if the wrong filament was lighting up on the passenger side.

I tried a different bulb. No such luck. Every time I switch on the brights the passenger gets dimmer while the driver side perfoms correctly. I mean significantly dimmer on the passenger side. It still gets very dim immediately when I hit the brights and then somewhat slowly gets a small amount brighter. I don't think there is a difference in brightness due to wire length.

[02_Legacy]

It sounds like me the ground wire for the high beam is not getting a good ground. You might have to follow it and see if there is a brake, or if it is fraying somewhere between the light and the switch.
To see if this will fix the problem you can take the wire Chuck pointed out in the pic and attach it directly to ground. If the high beam comes on than somewhere along that wire is your problem.

[toyota>subaru]

It sounds like me the ground wire for the high beam is not getting a good ground. You might have to follow it and see if there is a brake, or if it is fraying somewhere between the light and the switch.
To see if this will fix the problem you can take the wire Chuck pointed out in the pic and attach it directly to ground. If the high beam comes on than somewhere along that wire is your problem.

Yeah i'm glad you beat me to my question. I was going to ask which wire I can try grounding. Considering it hit a deer its definitely possible. I'll let you know how it goes.

[toyota>subaru]

Alright I went out and tried grounding the High beam wire to a bolt that went into the chassis.

With high beams on it had no effect. With high beams off it would make the driver side brighter and completely turn off the passenger.

Now by grounding the power wire or the low beam wire during "brights on" it would turn the pass. off and brighten the driver. Inversely it would Not make any noticeable changes during "brights off"

[02_Legacy]

Hmm that is interesting, I don't know if I can help you anymore. I might be able to figure it out with a wireing diagram, but unfortunatly I don't have one. Sorry

[toyota>subaru]

Yeah I don't have much experience with wiring diagrams but I think I could figure it out. Is there one that I can get that shows strictly the circuits from the box to the headlights?

[mike-tracy]

I take it you haven't downloaded the factory service manual? It's here:

viewtopic.php?f=14&t=20753 (https://sl-i.net/FORUM/viewtopic.php?f=14&t=20753)

An invaluable resource, and best of all, free - thanks to Chuck. It'll have everything you need.