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Discussion Starter #1
Hi all,

I'm sure this has been discussed, forgive my weak search skills. I have an '18 Outback Limited that I am installing a light bar on, ideally I'd like to have a switch that "arms" the light bar, then use a relay or something to turn the light bar with the high beams. I've managed to set this up on other vehicles, but I'd like to know if anyone has a proven method on the OB.

Thanks for your time.
 

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'15 Outback 2.5i Premium
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Hi all,

I'm sure this has been discussed, forgive my weak search skills. I have an '18 Outback Limited that I am installing a light bar on, ideally I'd like to have a switch that "arms" the light bar, then use a relay or something to turn the light bar with the high beams. I've managed to set this up on other vehicles, but I'd like to know if anyone has a proven method on the OB.

Thanks for your time.
Because the DRLs are the high beam lamps, this is not as straightforward as it could be. [Unless this changed with the '18 models, in which case I'm not sure.]

Presuming the headlight circuit for your '18 OB is the same as the North America spec '15 OB I have the wiring diagrams for, the best bet might be to tap the high-beam circuit between the dimmer stalk and the BIU (main computer). It shows as a Red/Green wire between pin 11 of 20-pin connector i73 on the combination switch on the steering column and pin 16 of 40-pin connector i171 at the BIU in the drawings. The switch works by grounding that wire to indicate to the BIU that high beams have been selected. This switch is not designed to handle much current; as a guess, it's probably adequate to operate a small relay, but no guarantee of that.

Simplest would be to 'arm' the relay by switching a 12V source on one side of the coil, and connecting the other side to a tap on the red w/ green stripe high-beam select wire. This has the issue that, when the switch is on, your light bar will turn on when the stalk is in the high-beam position whether the headlights are switched on or not.

I'd recommend getting that relay power by using something like an add-a-circuit fuse adapter in fuse 8 of the main fuse box under the hood (10A, 2015 model; YMMV). Doing that, if there's a fault in your added wiring, it won't blow the left high-beam headlight fuse; use the lowest-rated fuse you can get in the piggyback circuit. If you do that, the relay can only be active when the high beam bulb is getting power (DRL or high beam on) and the stalk has high beams selected (flash-to-pass or on).

Where you get the power for the light bar itself is the next question. How much current does it need? Perhaps you could use the same added circuit (size the piggyback fuse accordingly) or some other, like one of the power port circuits. I'd suggest using a source that's not live when the key is off so it doesn't drain your battery if your relay sticks.

Good luck!
 

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2016 Outback 2.5
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I have my light bar relay wired to the hi-beam fuse box under the hood, however be aware that because the DRL's are on the same circuit it will trigger your light bar when the headlights are off and the DRL's come on.

I have an override switch on the dash to turn off the light bar for that reason.
 

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18 Outback 3.6r Touring
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As the OP has an ‘18 with LED headlights, neither of these will work. The DRLs are a separate LED and The high beams are simply a flap in the projector that flips up. Maybe someone with stis subscription can provide some insight into tapping into that flap electronics.
 

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2015 OB Limited 2.5 Ice Silver Metallic
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I had set my last SUV like this. Worked with my 42" bar on the roof and 22" bar in my bumper. I used the Rigid Industries 3 way back up harness. Tapping into the high beam wire will trigger the relay to power the Light bars.

rigidindustries.com "Back Up Light Kit Harness (Dually/D2/Dually XL/D2 XL/SR-Q/ and SR-M)"

Works like a charm and I will be doing the same with my OB.

Hope that helps.

Fredy
 

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2015 OB Limited 2.5 Ice Silver Metallic
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Zedhead,

He asked for wiring suggestions, not light bars.
You would be pleased to see that the harness I recommended only costs $54. ;-)
The harness is compatible with any light bar/source out there.

Fredy
 

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Discussion Starter #9
Thanks Fredy, seem like a good option, when are you going to install on your OB? I'd be happy to let you go first! :)

The 3 way switch is a good idea, of, on, auto...
 

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Discussion Starter #10
As the OP has an ‘18 with LED headlights, neither of these will work. The DRLs are a separate LED and The high beams are simply a flap in the projector that flips up. Maybe someone with stis subscription can provide some insight into tapping into that flap electronics.
I wondered how that worked!

Certainly going to make things more difficult. Perhaps a simple on off switch will have to suffice.
 

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I wondered how that worked!

Certainly going to make things more difficult. Perhaps a simple on off switch will have to suffice.
Why would it make it more difficult? Same as the wire harness that turns on the bulb, instead it's only activating the flapper. Simple volt tester will work to determine which wire to jump.

Fredy
 

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As the OP has an ‘18 with LED headlights, neither of these will work. The DRLs are a separate LED and The high beams are simply a flap in the projector that flips up. Maybe someone with stis subscription can provide some insight into tapping into that flap electronics.
Is that right? Good grief! It sounds unnecessarily complicated, IMO, anyway.

A mechanical system covering and uncovering the headlights? What could possibly go wrong?
 

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Discussion Starter #13
I ended up having a mechanic familiar with modern vehicle electrical systems do the wiring install. He ended up using the power point under the arm rest as a key switched power supply for the light bar. There's a large hole in the firewall where the existing loom passes through, he made a slit in the grommet, installed the power wire for the lights and sealed things back up with some sort of sealing compound designed for such things. Manual on/off for the light bar rather than switched from the high beams. Works for me.
 

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