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2007 Forester XT 4EAT-VTD
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Discussion Starter #1
I have not done this yet but will begin gathering the few parts needed.

The mod is a simple one, but one that will IMO add tremendous flexibility to the deployment of the FXT's existing lights.

The plan is to intercept the low beam supply wire just before it reaches the lights and install a relay. The relay will be controlled with a swtich added to the cluster next to the fog light switch on the dashboard. For this, I am going to purchase another factory fog light switch and attempt to use that.

In use, the following lighting options would then be available. Options marked with *asterisk designate options enabled with extra switch.

Main light switch off -

1. DRLs on
2. DLRs off*

Main light switch turned to running light (middle) position -

1. Running lights on with DRLs
2. Running lights on without DRLs*

Main light switch turned to headlight position -

1. Running lights on with headlights
2. Running lights on without headlights*
3. Running lights on with fogs, no headlights*
4. Running lights on with fogs and headlights

With the extra switch in the open (off) position, it would be no different than having 2 blown low beam bulbs, which the circuit should be able to handle without any ill effect.

Let me know if you can think of any other potential complications/problems with this mod.
 

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2018 2.5i Premium CVT
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It ought to work as described, though since we use low side switching you would be interrupting the low beam ground wire. There is no low beam supply wire, only a common supply for both beams, separate for each side. (This assumes that 2007 also uses H4 bulbs, not separate highs and lows. If not, then disregard.) And you would of course have to insert the relay after the grounds from each side merged together (which might be kind of unreachable, buried inside a cable somewhere) or do it separately on each side.

The factory fog light switch will set you back about $25 or so, unless you can find a good junkyard (and tell me where it is!!!).

I did buy a factory switch for my 2003. The official nomenclature from the box says: SW ASSY [means 'assembly!'] INPANE F/F 83001SA000. Here's how it's configured, though YMMV.

With the switch in its normal orientation when mounted in the Forester, the bulge on its face is at the bottom, the picture of the light aims to the left, and the green bar light is at the top. Turning it around to the back this is what you'll see. The vertical bars are the terminals, and the numbers correspond to the wiring diagram. The dashes indicate that there is nothing in that space.

1 | | 3
--- | 4
--- | 5
2 | | 6

Here's how it's configured:

2 and 4 connect to the internal illumination light. This is the one that comes on when the headlights are on, to show you where the switch is. Polarity doesn't matter, but both terminals must use the existing illumination circuit or be totally separate, due to the way the illumination controller works. You could jumper these to 2 and 4 on the existing switch.

3 and 5 are the switch itself. Power comes in on 5 and goes out on 3.

1 is ground for the green bar light that comes on when the switch is on.

While the Forester wiring diagram shows nothing connected to 6, analysis of the switch itself shows that 3 and 6 are a second switch, isolated from the first. I guess it might serve some purpose if the same switch assembly is used in a different vehicle configuration.

The terminals on the switch are very small and deeply recessed. They don't match typical crimp connectors, so you might also pick up a matching socket. Off hand, this doesn't sound like a stock item, as it's probably part of a much larger harness assembly. One more reason to find a good junkyard!
 

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Premium Member
2007 Forester XT 4EAT-VTD
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2,145 Posts
Discussion Starter #3
Thanks for the info! I was concerned about the connectors on the back and it does sound like I'll need to track down the connector/harness.

Separate low beams/high beams on the '07, I planned on intercepting the low beam leads close to the bulb sockets. I would assume they could be tied together and ran through a single relay.
 

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2018 2.5i Premium CVT
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Separate low beams/high beams on the '07, I planned on intercepting the low beam leads close to the bulb sockets. I would assume they could be tied together and ran through a single relay.
I don't have a diagram of the 2007, but I think it's reasonable to assume that the fundamental wiring is unchanged and only broken out separately when it gets to the bulbs. So that ought to work as long as your relay is on the ground side of the low beams. They're already connected together there. It wouldn't work on the feed side, since left and right each get a separate feed.

But I'd be just a bit happier if I saw a diagram! Check everything out first with a meter to be sure.
 

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2007 Forester Sports XT 4EAT
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156 Posts
Has anybody figured out how to switch which lights come on as DRLs? I'd like to switch my DRLs to my high beams (I'd probably have to install a larger resistor to dim it more though). Or if someone has installed an LED strip they could use that as DRLs (Audi style). I remember seeing a wire diagram for the headlamp system, showing the controls and DRLs, but I never remember to save it!
 

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NA No more! :(
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8,529 Posts
^looking for the same--running alternative lights as DRLs, and possibly left on while low beams are on.
 

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2008 Forester AE
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1,726 Posts
nice, I was just thinking of what it would take to do this..
I was on the relay on the DRL module line of thought but this would allow more options..
I would try to have the relay wired open when the headlights are on; when the switch is 'on' the relay 'on' opens the connection and the lights go out.

count me subscribed
 

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MY08 XT
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370 Posts
I don't have a diagram of the 2007, but I think it's reasonable to assume that the fundamental wiring is unchanged and only broken out separately when it gets to the bulbs. So that ought to work as long as your relay is on the ground side of the low beams. They're already connected together there. It wouldn't work on the feed side, since left and right each get a separate feed.

But I'd be just a bit happier if I saw a diagram! Check everything out first with a meter to be sure.
MY07 headlight diagrams (Non HID version) as follows...






 

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Thanks for the 2007 diagram, skippy124. It looks remarkably like the diagram for the H4-equipped Foresters except for there being two separate bulbs on each side rather than one dual-filament one. But if you imagine that the assemblies called "Headlight RH" and "Headlight LH" were instead called "H4 bulb", I think it would be the same thing. So all previous advice stands.
Each side is fed separately to a common point on the (electrically) high side of the bulb assembly.

The (electrically) low side of each beam is connected together, left and right, and then switched to ground through a complicated mix of relays and switches.​
 
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