Driving Light Wiring
Discussion
Have posted this question in the Subaru forum but could be be a view here......
So having cleaned up the headlights of my '04 wagon, aligned them properly and fitted Osram bulbs, I'm still of the view that they're not good enough for what I need.
Impreza has useless front fog lights in the front bumper, an option back in the day was to replace those with top quality driving lights so here we go;
So I've tracked down some of the original Prodrive brackets for this later car and PIAA driving lamps to replace the fogs. I plan to use the existing front fog light switch as a control to activate the driving lamps with main beam only (or not) as required, I don't want any new switches and am keen to keep it all looking as standard as possible.
I've been scratching my head with the wiring options and don't want to touch the main loom or muck about with the switch so I've come up with this using two simple switching relays that I can hide out of the way.
Apologies for the crude sketch but happy to hear any comments especially if you think I can simplify the wiring. The new driving lights draw 260 watts in total hence the 25amp supply to relay 2. The supply from the main beam circuit to relay 1 will draw virtually nothing but I've popped in a 5amp fuse to show willing.
So having cleaned up the headlights of my '04 wagon, aligned them properly and fitted Osram bulbs, I'm still of the view that they're not good enough for what I need.
Impreza has useless front fog lights in the front bumper, an option back in the day was to replace those with top quality driving lights so here we go;
So I've tracked down some of the original Prodrive brackets for this later car and PIAA driving lamps to replace the fogs. I plan to use the existing front fog light switch as a control to activate the driving lamps with main beam only (or not) as required, I don't want any new switches and am keen to keep it all looking as standard as possible.
I've been scratching my head with the wiring options and don't want to touch the main loom or muck about with the switch so I've come up with this using two simple switching relays that I can hide out of the way.
Apologies for the crude sketch but happy to hear any comments especially if you think I can simplify the wiring. The new driving lights draw 260 watts in total hence the 25amp supply to relay 2. The supply from the main beam circuit to relay 1 will draw virtually nothing but I've popped in a 5amp fuse to show willing.
Great stuff, thank you!
You're quite right, I want the spots to only work with the high beam but retain the option to turn them off.
I'm trying to avoid touching any of the existing switch wiring and hope to do all of this from under the bonnet. I can't imagine I'd ever want or need to go back to standard but this makes it much easier.
I don't know enough about what other relay options are out there, I grew up using the old Lucas 6RA for everything! Hoped there might be one unit out there that could do the job of two!
Good point about how the existing lights are powered/switched. I've made a big assumption there and was simply planning to take an activation feed from a high beam supply behind the headlight. Will check when I start the job this weekend.
More than happy to go with protocol over terminal use, us amateurs can't be trusted!
You're quite right, I want the spots to only work with the high beam but retain the option to turn them off.
I'm trying to avoid touching any of the existing switch wiring and hope to do all of this from under the bonnet. I can't imagine I'd ever want or need to go back to standard but this makes it much easier.
I don't know enough about what other relay options are out there, I grew up using the old Lucas 6RA for everything! Hoped there might be one unit out there that could do the job of two!
Good point about how the existing lights are powered/switched. I've made a big assumption there and was simply planning to take an activation feed from a high beam supply behind the headlight. Will check when I start the job this weekend.
More than happy to go with protocol over terminal use, us amateurs can't be trusted!
Sorry for bringing an old thread back from the dead but it seemed the best answer to what I was doing. Essentially, like the OP, I want to use my existing fog switch alongside the high beam feed to trigger aux lights on my Impreza.
However, I have discovered that the lighting circuit on the car is switched ground. Is it literally as simple as taking the feed to the first relay from the earth side of the fog and high beam and leaving everything else ‘as is’, or is it more complicated than that? My working knowledge of auto wiring is relatively minimal so questions like this definitely throw me a bit!
Cheers.
However, I have discovered that the lighting circuit on the car is switched ground. Is it literally as simple as taking the feed to the first relay from the earth side of the fog and high beam and leaving everything else ‘as is’, or is it more complicated than that? My working knowledge of auto wiring is relatively minimal so questions like this definitely throw me a bit!
Cheers.
Yes. Exactly the same as the OP, I want to use driving lamps and wire them so they’re only on if the switch is on and full beams are on. As with the OP I also don’t want to hack into the wiring. Given I have a front fog lamp switch and fog lamp circuit doing nothing it would seem a neat and tidy solicitor to use this as with the OP’s diagram. The only issue with that diagram is that it appears to be for switched power rather than switched earth and I’m struggling to find an answer as to whether the proposed solution works for this, and if it does, which wires you splice into.
Mechanics I’m fine with, it’s the electrics side I’m less sure of, particularly when you throw in switched ground systems!
Mechanics I’m fine with, it’s the electrics side I’m less sure of, particularly when you throw in switched ground systems!
I have a Blob WRX and got a bulb extender (HB3 iirc?), put that into a relay and then put that onto some driving lamps on the bumper using a piece of metal and screwing into the front numberplate mount then wired them from the relay to the battery, didn't take too long to do.
Ended up replacing the 200w spotlights with some Cree XHP 70 lights meant for a motorbike which are small and discreetly fit in the front grill, they only use 36 watts each so if doing it again I'd replace the main beams with LED's and wire in some external LED's and not use any relays, the LED's easily increase the useable range 3-4x compared to the Halogens.
Ended up replacing the 200w spotlights with some Cree XHP 70 lights meant for a motorbike which are small and discreetly fit in the front grill, they only use 36 watts each so if doing it again I'd replace the main beams with LED's and wire in some external LED's and not use any relays, the LED's easily increase the useable range 3-4x compared to the Halogens.
There is one problem that may need solving and only you can prove if it's there or not
Sometimes when a relay is added to the main beam circuit it won't operate as expected
What happens is that the relay clicks in as expected when the lights are on main beam and the fog light switch (or whatever switch is used) is operated, sometimes the daytime running lights circuit, volt-drop or circuit fault interferes with the operation of the relay and holds it in when the fog light switch (or whatever switch is used) is switched from on to off
You're best checking all is well before getting stuck into wiring everything up. If you decide not to check the above before wiring everything up and there's a problem, alterations will have to be made to get the circuit working correctly. Your choice
Choose which main beam headlight plug (LH or RH) is easiest to run a cable from to the bulkhead and onwards through to the interior, there will surely be a grommet somewhere
Test that this main beam headlight circuit will operate a relay correctly
Using one of these will help in testing and later in wiring up if you don't want to cut into your Subaru wiring
https://www.amazon.co.uk/Headlight-Components-Conn...
Going by the below info
It can be seen that a Red cable is the switched Negative to LH and RH Main Beam Bulbs
It can also be seen that the LH Supply cable is Red/Blue and RH Supply cable is Blue/White
Using the above adapter lead (strip some sleeving back), or by shoving cables up the rear of the headlight plug or by stripping some sleeving off the Subaru plugs wiring
Find some cable you have lying around
Connect a cable from a Red headlight bulb cable to a 4 Pin relay Terminal 85
Connect a cable from Red/Blue or Blue/White depends on which side (LH or RH) you chose to the same 4 Pin relay Terminal 86
Have someone sit in the car and start it, with the relay held in hand ask for
Switch side/tail on - Relay shouldn't click in, you will feel it and likely hear it if it does
Switch headlights on making sure headlight stalk is set to dip - Relay shouldn't click in, you will feel it and likely hear it if it does
Select main beam with stalk - Relay should click in
Select dip beam with stalk - Relay should click out
And then
Select main beam with stalk.......Relay clicks in..........Switch side/head switch back one position to side/tail - Relay should click out
Looks much work yet there's very little to it, pain to explain though, all you will be doing is connecting a relay up to the Subaru main beam wiring to prove it will definitely switch on/off and that it never holds in when not on main beam
Wiring it all up is not too complicated once you know all is ok with the above
Will go through the rest once all is proven ok
Post back here
Sometimes when a relay is added to the main beam circuit it won't operate as expected
What happens is that the relay clicks in as expected when the lights are on main beam and the fog light switch (or whatever switch is used) is operated, sometimes the daytime running lights circuit, volt-drop or circuit fault interferes with the operation of the relay and holds it in when the fog light switch (or whatever switch is used) is switched from on to off
You're best checking all is well before getting stuck into wiring everything up. If you decide not to check the above before wiring everything up and there's a problem, alterations will have to be made to get the circuit working correctly. Your choice
Choose which main beam headlight plug (LH or RH) is easiest to run a cable from to the bulkhead and onwards through to the interior, there will surely be a grommet somewhere
Test that this main beam headlight circuit will operate a relay correctly
Using one of these will help in testing and later in wiring up if you don't want to cut into your Subaru wiring
https://www.amazon.co.uk/Headlight-Components-Conn...
Going by the below info
It can be seen that a Red cable is the switched Negative to LH and RH Main Beam Bulbs
It can also be seen that the LH Supply cable is Red/Blue and RH Supply cable is Blue/White
Using the above adapter lead (strip some sleeving back), or by shoving cables up the rear of the headlight plug or by stripping some sleeving off the Subaru plugs wiring
Find some cable you have lying around
Connect a cable from a Red headlight bulb cable to a 4 Pin relay Terminal 85
Connect a cable from Red/Blue or Blue/White depends on which side (LH or RH) you chose to the same 4 Pin relay Terminal 86
Have someone sit in the car and start it, with the relay held in hand ask for
Switch side/tail on - Relay shouldn't click in, you will feel it and likely hear it if it does
Switch headlights on making sure headlight stalk is set to dip - Relay shouldn't click in, you will feel it and likely hear it if it does
Select main beam with stalk - Relay should click in
Select dip beam with stalk - Relay should click out
And then
Select main beam with stalk.......Relay clicks in..........Switch side/head switch back one position to side/tail - Relay should click out
Looks much work yet there's very little to it, pain to explain though, all you will be doing is connecting a relay up to the Subaru main beam wiring to prove it will definitely switch on/off and that it never holds in when not on main beam
Wiring it all up is not too complicated once you know all is ok with the above
Will go through the rest once all is proven ok
Post back here
Ennoch said:
The test will be the same (once the relays and bits I ordered arrive) but I just clocked the wiring and those adaptors are for the Bugeye - the Blobeye uses separate bulbs for main (HB3) and dip (H1).
Oh noMy apologies
If you're stuck with those adapter leads I will do something for you, didn't give it a thought, was thinking about twin dip/main headlights
Yes the test remains the same, test at the main beam
Penelope Stopit said:
Oh no
My apologies
If you're stuck with those adapter leads I will do something for you, didn't give it a thought, was thinking about twin dip/main headlights
Yes the test remains the same, test at the main beam
No stress at all, the wonder of Amazon’s returns! I’ve sorted out a return and ordered the hb3 extenders so it’s all good. It’ll probably be next week now before I get a chance to test but as it’s about the time of year I start doing long drives early morning/late night I’ve got a good incentive to sort it out ASAP! Thanks again. My apologies
If you're stuck with those adapter leads I will do something for you, didn't give it a thought, was thinking about twin dip/main headlights
Yes the test remains the same, test at the main beam
Ok then
In 2 or 3 days time or....
Think what I'll do is post up a wiring job taking it that the test proves good and another wiring job that has proved to be reliable if the test shows the relay to be holding in when it shouldn't be
Will you be fitting the relay/relays in the engine bay or inside the car?
1 or 2 relays is the other thing I'll need to know
1 relay will do the job
In 2 or 3 days time or....
Think what I'll do is post up a wiring job taking it that the test proves good and another wiring job that has proved to be reliable if the test shows the relay to be holding in when it shouldn't be
Will you be fitting the relay/relays in the engine bay or inside the car?
1 or 2 relays is the other thing I'll need to know
1 relay will do the job
Is your switch the same as this?
Colours the same as these? (Ignore text in brackets for now)
5 Pin Switch Could Be 6 Pin
1 - Red/Green (Permanent Connection To Warning Light For Driving Lights)
2 - Orange/White (Switch Illumination)
3 - Black/White (Switch Contact 2 Also Switches To Warning Light For Driving Lights)
4 - Violet (Switch Illumination)
5 - Yellow/Blue (Switch Contact 1)
Colours the same as these? (Ignore text in brackets for now)
5 Pin Switch Could Be 6 Pin
1 - Red/Green (Permanent Connection To Warning Light For Driving Lights)
2 - Orange/White (Switch Illumination)
3 - Black/White (Switch Contact 2 Also Switches To Warning Light For Driving Lights)
4 - Violet (Switch Illumination)
5 - Yellow/Blue (Switch Contact 1)
Edited by Penelope Stopit on Friday 22 November 15:13
Penelope Stopit said:
Ok then
In 2 or 3 days time or....
Think what I'll do is post up a wiring job taking it that the test proves good and another wiring job that has proved to be reliable if the test shows the relay to be holding in when it shouldn't be
Will you be fitting the relay/relays in the engine bay or inside the car?
1 or 2 relays is the other thing I'll need to know
1 relay will do the job
The answer seems to be that it doesn't switch the relay. However, it's a 5 pin relay rather than 4 as I ordered the wrong ones. My understanding was that this shouldn't make any difference as you still connect to pin 87 for the power output. Not sure if that's actually correct though and whether it would have any effect on this test? In 2 or 3 days time or....
Think what I'll do is post up a wiring job taking it that the test proves good and another wiring job that has proved to be reliable if the test shows the relay to be holding in when it shouldn't be
Will you be fitting the relay/relays in the engine bay or inside the car?
1 or 2 relays is the other thing I'll need to know
1 relay will do the job
The intention is to have the switch on the interior (discovered a gromet that led straight to the switch panel), and have the relay in the engine bay. It should therefore be quite simple, but not knowing the impact of the switch earth on the logic is definitely throwing me!
Thanks again
Ennoch said:
Given I have a front fog lamp switch and fog lamp circuit doing nothing it would seem a neat and tidy solicitor to use this as with the OP’s diagram
Took this to mean that there is a Subaru fog lamp switch already fitted and you wanted to use it for driving lightsEnnoch said:
The answer seems to be that it doesn't switch the relay
Applying 12 volts from a main beam bulbs wiring to terminals 85 and 86 of a 12 volt 5 pin standard relay will definitely switch the relayThe test is to prove that the relay never holds in when on dip or side
Ennoch said:
However, it's a 5 pin relay rather than 4 as I ordered the wrong ones. My understanding was that this shouldn't make any difference as you still connect to pin 87 for the power output. Not sure if that's actually correct though and whether it would have any effect on this test?
Yes you're on the case, 5 pin relays aren't a problemEnnoch said:
Sorry, missed the last post as it didn't show up when I was replying. The switch I have is a simple 2 pin aftermarket one.
Ok then, so your not using a Subaru fog lamp switch that's already fitted as mentioned aboveThe jobs very simple if your using a 2 pin switch
Once again test that the relay is switching in and out as in the earlier posted test
If the relay never switches in the relay itself will very likely be faulty as long as it's a standard 5 pin one
Will post a diagram later or in the morning showing a 2 pin switch
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