Help me with this one:

I've got the LHD STi Projectors, some Hella DE fogs wired into the stock fog harness, and some Hella 500 driving lights. Here's what's supposed to happen:

Switch light on: Lo beam on
Switch Highs on: Lo *and* Hi beams on
Fog's work only when Lo's are on and highs are off
Driving lights work only when Hi's are on

I got all this working, *except* for this freaky occurance:

Turn the Lo's and fogs on,
switch hi beams on (fogs go off),
turn off hi beams (fogs come back on)
BUT the highs are still on!!

Everything works as expected if the fogs are off. Some how the fog lights are tripping my hi-beam relay... why!???

I'll scan my as-built wiring diagram when I get home from work so you can see what I'm talking about.

In the meantime, does anyone have the wiring diagram for the WRX headlights and foglights? Can someone scan that page out of the manual for me?

hm...I have similar problem though I got H4 dual beam HID
when fogs on and low on, switch to high, then go back to low > fogs on, low off....

idea was grounding issues, but seems to be fine

how come when you put your high beams both your low and high beams come on? how did you wire everything in? can you just post how you wired your relay for your hella 500s?

If I'm not mistaken, on the STi projectors, both lamps are *supposed* to be lit when the hi-beams are switched on, right? At least the hi-beam pattern on my projectors only lights up _above_ the low beam pattern... so if only the hi-beam is on, I have no on-road light.

Anyway, I got my stuff working, but to be honest, I'm not sure why it works. I have a relay wired on one of the lights to provide power to the low beam lamps when the hi's turn on. The other light is wired so only the hi-beam is on when the hi's are switched on... since the lights are in parallel, somehow everything now works. :lol: I can't say why it works unless someone can hook me up with a stock wrx wiring diagram.

As for my Hella 500 driving lamps, I didn't use the wiring harness that came with it. Since I got some Hella DE's that I wired to the stock fog light harness, I had the really nice DE harness that I used for the Hella 500s. The only trick is wiring it so it only comes on with the hi-beams. The way I got it to work w/ my stock lights was to wire the hi-beam signal line connected to the *lo-beam* ground, right at the left head light. That way, when the low-beam is off the common positive sends power to the Hella's relay allowing the switch in the dash to turn them on.

In my new setup, I have the hi-beam signal line connected to the positive output from my added relay that's on when the hi-beams are on. That was pretty straight forward.

Here's my wiring diagram... sorry my handwriting is so bad :D This is how my car is currently wired, and as I said above, I'm not totally sure how it works (but it does) because I don't know the stock wiring. In this setup, the lo-beams are on with the hi-beams, the fogs won't work with the hi's on, and the driving lights (Hella 500's) won't work *unless* the highs are on. Get it? :lol:

http://www.seccs.org/images/misc/sti_projector_wiring_diagram.jpg

--Scott

the way you have it now is better, but can still be optimized. if i was reading it right before you had the low beam providing the 12V for the Hella 500s, so when the low beam got turned off when it went into high beams that wire would go to 12V. the way i wired my hella 500s is i hooked up the 85 and 86 terminals to the common power and red switched high-beam wire (with diode across the terminals), then 30 to the battery with fuse and 87 to the hella 500s. even thouhg 85 and 86 are both at 12V, there is no current flow so the relay stays open. but since they're both at 12V, you need to put a diode to suppress extra current when energizing/de-energizing the coil. i think that's how you have it wired up now seeing the relay with the blue and red wires. unless you're getting power from the blue wire also. just to double check, all your relays should be hooked up to the battery to get the correct light output.

oh yeah, what's the chassis ground on the right side that looks like it's connected to the low beam ground?

I guess I need to replace that relay with one that's got a diode built in (I'm done soldering for a while now.. hehe).

The "To Hella 500s" wire goes to yet *another* relay in the Hella 500 wiring harness. They are powered straight from the battery the way you described. That wire is just to tell when the hi-beams are switched on.

The chassis ground *is* connected to the switched lo-beam ground. This is one of the things I'm confused about, since I don't know what's really going on on the stock side of things. All I know is that I needed a ground for the lo-beams when the hi-beams are on. Basically, because of the chassis ground, whenever *any* lights are on, the lo-beams are grounded and therefore turn on. I tried this without connecting to the lo-beam switched ground, and the headlights worked, but the fog lights would never come on because they always thought the lo-beams were off. With this crazy setup, the fogs are on only when the lows are on, as per standard operation.

BTW: Can you explain the need for the diode a bit more, I'm not sure I understand the need.

--Scott

the diode is there because you have the 85 terminal at 12V and the 86 thermal at 12V. so lets say you have the red high beam switched ground at the 86 terminal. when you turn the high beams on, the 86 goes to 0V and you get current across the 85 -> 86. when you turn them off, the 86 goes back to 12V. the diode protects against current surges when this happens. i'm sure mulder and netz can explain this better.

oh so you connected the ground to the low beam and that's how you got the low beam to come on with the high beam. hmm that doesn't really sound that good. if you have your high beam on, the yellow low beam wire will be at 12V, but you have a chassis ground connected to that wire and should cause a short, so i'm not sure why it works. also if you do it that way with both low and high on at the same time, they're sharing the same power source (blue wire), so you might have problems with the small wire, also you're pushing the amp limit of the headlight relay i'm guessing. might want to rethink the wiring a bit. you can add extra relays to power the low and highs directly from the battery using the yellow and red wires for controls. gimme a few minutes and i'll have a wiring chart for it

oh yeah, you can buy relays with diodes already wired into them. radioshack should have them, i order my stuff from partsexpress.com because i buy about 10 at a time.

to turn on low beams in any condition.
85- ground
86- blue common power
30- battery
87- low beam

this won't rely on the switched ground wires so this is the most simple way to do it.


to turn on high beams
85- 12V (can use the blue common power)
86- red switched high beam ground
*diode across 85 and 86
30- battery
87- high beam

this is pretty much just copying the stock system except it gets power from the battery and not the blue common power wire.


to turn on hella 500s with high beam, you can just copy the above wiring, or do it this way:
85- ground
86- 87 terminal of the above relay
30- battery
87- hella 500 driving light

grabbing the 87 terminal to control this relay isn't that bad because relays only grab <1amp of current, so whichever way you want to do it.


hella micro de's connected to stock wiring should work just like the stock fogs, on when low beams are on only.


*i forgot, you have to tap into these wires before they split off into each headlight for best results, or else the driver's side headlight might be a bit brighter than the passenger one but not 100% sure about that. also use at least a 15amp relay.

to turn on low beams in any condition.
85- ground
86- blue common power
30- battery
87- low beam

this won't rely on the switched ground wires so this is the most simple way to do it.
I tried it close to this way, and the fog's won't come on unless the lo-beam switched ground is part of the circuit. :mad:


to turn on high beams
85- 12V (can use the blue common power)
86- red switched high beam ground
*diode across 85 and 86
30- battery
87- high beam

this is pretty much just copying the stock system except it gets power from the battery and not the blue common power wire.
I like this.


to turn on hella 500s with high beam, you can just copy the above wiring, or do it this way:
85- ground
86- 87 terminal of the above relay
30- battery
87- hella 500 driving light

grabbing the 87 terminal to control this relay isn't that bad because relays only grab <1amp of current, so whichever way you want to do it.
That's how it is now. :)


hella micro de's connected to stock wiring should work just like the stock fogs, on when low beams are on only. That's my only concern... I don't think this is true. :confused:

Hey, thanks for all the help!! If you're interested, I got some pics of the lights here: http://www.seccs.org/gallery/index.php?gallery=//gallery/Car%20Pictures/Doink%20WRX/LHD%20STi%20Projectors

--Scott

hmm yeah you'll probably need to lookup how the fog light relay is wired. i can't remember because i've never played around with it personally. if we can find the schematic we can just change the controls on the relay under the dash for the fogs. i know there's something funky going on because of the drl circuit and the high beam restriction, but can't tell you off the top of my head how it works. good luck, i'll post a thread if i run across it.

Originally posted by tdxflex
hmm yeah you'll probably need to lookup how the fog light relay is wired. i can't remember because i've never played around with it personally. if we can find the schematic we can just change the controls on the relay under the dash for the fogs. i know there's something funky going on because of the drl circuit and the high beam restriction, but can't tell you off the top of my head how it works. good luck, i'll post a thread if i run across it.

Yeah, I need a copy of the wrx wiring diagram for the headlights and fog lights from the service manual.

Make it easy on yourself.

Wire one relay coil +/- to the Subaru wiring harness +/- for high beam....another the same for low beam. Use multi-switch relays (or multiple relays). Now run a fused, large + power from the battery to power the lights through the relays. Power on the input of every switch, outputs to each individual light. If this were my car, I'd run high beam power to every light in the cluster and low beam power just to the low beams....but that's just me. Your harness will like you and your lights will have all the current they need. Oh, and ground the other side of all your lights.

jack

Originally posted by Jack ffr1846
Make it easy on yourself.

Wire one relay coil +/- to the Subaru wiring harness +/- for high beam....another the same for low beam. Use multi-switch relays (or multiple relays). Now run a fused, large + power from the battery to power the lights through the relays. Power on the input of every switch, outputs to each individual light. If this were my car, I'd run high beam power to every light in the cluster and low beam power just to the low beams....but that's just me. Your harness will like you and your lights will have all the current they need. Oh, and ground the other side of all your lights.

jack

I'm having trouble understanding how to get the Lo and Hi beams to turn on with the high beam switch in this setup. Can you be a bit clearer? It sounds like you're suggesting I wire each of the common positive / switched ground pairs to a relay. That will convert the negatively switched system into more of a positively switched setup, but won't provide power to the Lo beam light when the hi-beams are on.

--Scott

sperry: It's true that the stock fog relay is wired in such a way that it draws its (small) current through the high-beam bulbs when those are off. But with your setup, most of this current would be passing through the right-side bulb, because in place of the left bulb, you have a relay coil, with much more resistance than the bulb. By any chance, could the right-side high beam be burnt out?

Okay, wiring attempt version 4... this is *it*.

The problem with the fogs and high beams etc. boils down to the high beam relay latching on due to back-flow of current from the fog lights.

tdxflex is the man, diodes correctly positioned across the relays fixes the issue!!

Here's my latest setup... both lights are wired like this:

http://www.seccs.org/images/misc/sti_projector_wiring_diagram_correct.jpg

Note the diodes on the relays to prevent back-flow from the fogs incorrectly triggering the relays.

So, everything works, and everything makes sense... at least on this side of the stock wiring... I'm still not sure why or how the fogs are wired the way they are... but this works, and I've got good seperation for the lights from the stock harness, so I shouldn't melt anything running around with highs and lows on together.

--Scott

One more update...

Turns out there's still an issue with the driver's side high beams latching on if the fogs are on. Now it's intermittant... but it still happens.

Luckily I figured it out... the goddam LED in the fog light switch is powered by the driver's side high-beam ground!!!! What an AWFUL design! This means on a stock WRX, if the driver's side bulb burnt out, the fog light LED would stop lighting... :lol:

Basically, as you can see in the above diagram, if the LED were on the red high-beam switched ground, then the current it draws is enough to keep the high-beam relay switched on when you turn off the high-beams.

To fix this, I cut the wire leading to the LED and hooked the switch up to the +V that's on when the lights are on. My LED isn't quite accurate, since it's on if the DRLs are on and the switch for the fogs is on, even tho the fogs don't run with the DRLs. Perhaps I'll do the fog light mod to allow that to work... then my LED will be accurate.. :lol:

--Scott