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2003 XTi Cross Sports 4EAT :(
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Discussion Starter · #1 · (Edited)
I purchased a new little relay, very cool design which should aid us HID users greatly. Especially for Bi-Xenon users.

Here is a link to the relay that I purchased and the info on it.

Here is my go at it with some information from the manufacturer website:



Here is a blank template to "connect the dots" for my relay diagram:



Please tell me if I did it right or if there is a better way please connect the dots for me!

Thank you.

Edit, Installed relay:

 

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2009 Outback XT-B 5MT
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Why does "1" split from the H4 connector to the + on the bulb solenoid AND 1 on the new relay?

That means that, no matter what, the + on the bulb solenoid is going to be getting power.
 

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Discussion Starter · #3 · (Edited)
Oops, see this is why I posted. Thanks for pointing out my mistake! It should go from 2.

I will fix that and assuming if I do should it then be correct?

EDIT: Fixed, new image uploaded.
 

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2009 Outback XT-B 5MT
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Right. So when 2 is hot, the high beams are on. When 2 is cold (and 1 is hot), the low-beams are on.

The whole point of the relay is to buffer the "switch off" delay when switching to the high-beams.

I presume you'll be using a single relay per side, correct?

I would ground everything that needs a ground to a clean metal bolt and NOT the ground pin on the H4 harness. Keep the wiring as short as possible.
 

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Discussion Starter · #5 ·
I was going to use a single relay since the specs claim it can power two ballasts no issue, but they are fairly inexpensive so ordering another isn't out of the question if you think that would be better.

If everything on my diagram looks OK I may try a rough design out and if all is well build it up with two relays using some thicker wire than stock and minimizing the cable run lengths.

So I should ground to the engine bay / battery (whichever is closest) not the harness and there shouldn't be any issues? I guess it is all a common ground source anyways so it shouldn't matter.
 

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I can't say that I completely understand this, but it appears to assume that the stock H4 connector provides separate + feeds for high and low beam, and then goes to a common ground. That's a common assumption by aftermarket devices, and backwards of how Subarus are wired. The common H4 terminal is + when either high or low beam is enabled (including DRL), and the beams are selected by grounding their respective terminal (through a resistor in the case of DRL).

Perhaps the "Positive Trigger" and "Negative Trigger" thing over at the far right might be addressing this, but I'm not sure how to read it.

Here's the pinout, looking into the connector:


Low


High............Common
 

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Discussion Starter · #7 ·
The relay I have can be used with either positive or negative side switching. There is a selector switch for what type is needed on the back so I am assuming it should work without issue as long as my wiring looks right.
 

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OK, that matches the pin configurations. The problem was with the nomenclature in the diagram (G on the common H4 terminal) and with Phil's (BAC5.2) use of the terms hot, cold, and ground.

You will probably have to disconnect the DRLs to avoid confusing the relay.

Per the manufacturer's description, you should be able to save yourself $5 by buying the negative switching model rather than the one that goes either way.
 

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Discussion Starter · #9 ·
I will get to work on assembly (already have the relay) and let everyone know how it goes. I have already disabled the DRLs so I guess I should be good to go.

Thanks for the clarification and suggestions.
 

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Discussion Starter · #10 · (Edited)
Update, the relay is installed and "works"... BUT.

The high beam only works if the passenger harness on the car has a ballast or halogen bulb directly connected. (The relay is on the driver side harness.) Without it, the driver side harness doesn't trigger the high beam on the relay

I'm confused, it seems like I need some sort of dummy connected to the other harness with some kind of load. But the weird part is, I connect a ballast directly to make it work, but the ballast only connects to the low beam wires (connectors G1 & H in my diagram at the top of this thread), nothing to do with the high beam wires, yet it seems required to make it work which makes no sense to me.

I'm thinking I need a resistor to simulate load on the low beam, I just don't know what to get.
 

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2014 Impreza Ltd CVT
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nope, the bulb in place on the passenger side high beam 'allows' a small amount of current to flow for the foglight relay. This relay is used in conjunction with the High beam relay and needs some amount of current to flow to pick it.

I suspect your time delay relay does not allow any or enough current to flow since it's probably a solid state device ( transistor, diode or other semiconductor ) inside.

I might try a 20 ohm 10 w resistor across each of the G2 to H and G1 to H to allow some current to flow when the selected 'bulb' is in the OFF position.

Others have had similar problems when they use a high current harness where the high/low power simply picks a relay which has heavier wires running to higher amperage connectors for higher wattage bulbs. The current passed thru the unlit bulb is used to power low voltage relays. Now they have 2 relay coils in series, sometimes neither one will pick, sometimes they both do.
 

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That wasn't an either-or question. Need to know which. While this isn't a job I've done myself, I can recall reading here that the module has to be removed when you go to HIDs.
 

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Discussion Starter · #15 · (Edited)
nope, the bulb in place on the passenger side high beam 'allows' a small amount of current to flow for the foglight relay. This relay is used in conjunction with the High beam relay and needs some amount of current to flow to pick it.

I suspect your time delay relay does not allow any or enough current to flow since it's probably a solid state device ( transistor, diode or other semiconductor ) inside.

I might try a 20 ohm 5 w resistor across each of the G2 to H and G1 to H to allow some current to flow when the selected 'bulb' is in the OFF position.

This makes a lot sense now that you explain it. The relay is solid state so no current would make sense to me.

Resistors are cheap, I could make a dummy plug for the passenger side. I'll pickup some at radio shack tomorrow and try it.

(could I damage the stock harness if I don't have enough resistance? I'm assuming yes.)

That wasn't an either-or question. Need to know which. While this isn't a job I've done myself, I can recall reading here that the module has to be removed when you go to HIDs.
Oops! Fixed my previous post, DRL resistor is disconnected. I didn't try connecting it to see if it bypassed my issue.

EDIT:

Looks like the DRL resistor being unplugged has no effect with the new relay. DRL still comes on. Time to pull the module!
 

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An alternative is to go for a wholesale rewiring of the fogs and the headlights. It would end up being a lot simpler than what's there now!
 

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Discussion Starter · #17 · (Edited)
For now I will try out the resistor.

I've been looking online at resistors for HIDs and things of that nature.

50w @ 6ohm seems to be the most common but that is usually in conjunction with a ballast or an LED bulb. I don't know how it will work on its own.

ferret suggested a 20ohm 5w resistor but from what I have read about resistors, 5w might be too low since this circuit usually works with 55w halogen bulbs.

An excerpt from some info on resistors:

"One last important note about resistors is their wattage rating. You should not use a 1/4 watt resistor in a circuit that has more than 1/4 watt of power flowing.

For example, it is NOT okay to use a 1/4 watt resistor in a 1/2 watt circuit. However, it is okay to use a 1/2 watt resistor in a 1/4 watt circuit."
 

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I stand corrected, My 20 ohm should have been 10w .... I just re read this. 20 ohm should be just over a 1/2A current draw and 1/2A x 12v is 6W. but they don't make 6w resistors.

A new entry in this thread ensures it is read, AND I will correct the first post as well.
 

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I'm not following these numbers at all, Mikey. Please clarify.

A 20 Ohm resistor at 13.8 volts pulls a current of 0.69 amps and dissipates 9.52 watts.

Or, if we're attempting to match the resistance of a 55 watt bulb in order to allow enough current to flow for the fog light relay, we're looking at a resistor of 3.45 ohms, which will allow a current of 3.99 Amps and dissipate, voilà, approximately 55 watts!

And to the OP, the wattage rating on a resistor isn't an electrical property. It's a rating of how much heat the resistor can safely dissipate without harming itself. It's always wise not to cut this too close.

(Mikey knows my philosophy regarding production of unnecessary heat, but we won't get into that here.)
 

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Bruce, we only want enough to allow the relay coil to pick, remember an unlit 55w bulb passes enough current to allow the relay coil to energize without using enough to emit light. So I'm not trying to replace the load ( 55w) with the same load, but a smaller load that will not dissipate a lot of heat, but enough to pick a 150-200 ma coil.

Maybe I'm not understanding your concern completely ...... PM me and we'll pick it up there. As always, if I'm not correct, I'll fix the posts for future reference.
 
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