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Driving Lights Help!!!

I[OIIIIIIIO]I

Active Member
Messages
43
Location
Grand Rapids, MI
I just installed some new driving Lights and I want to trigger them to turn on with the hi beams.

I thought this would be very simple as in the past I have just tapped into the headlight wires or fusebox for a hi beam positive lead.

However, I have had no luck figuring out how to do this on the H3 because it seems that the headlights use a switched ground.

I am not familiar with how to tap into this system for what I want to achieve.

Does anyone know where I can find a positive lead that is triggered by the high beams or how to use the switched ground?

I just want the simplest way to have the driving Lights come on with the hi beams using the factory headlight stalk.

Any suggestions???

And yes, I did try to search first and I didn't find anything.

Thanks in advance!
 

Mcssls

Member
Messages
24
Location
Albuquerque New Mexico
Is the high beam at the bulb + or - trigger? Either way you can tap there to a simple relay. Look up online. A relay can be triggered either way and would not draw power from the light circuit. Instead you could have it draw directly from the battery which has benefits, this can also be done to the headlights themselves. It can improve lighting output a little.
 

adventuredad

Well-Known Member
Messages
86
Location
Southwest WA
You are correct, it looks like the stalk switch is switching ground instead of positive. The best way to go about it would be to add a relay into that circuit and then power your driving lights off that.
Screen Shot 2019-03-27 at 7.32.10 AM.png
 

I[OIIIIIIIO]I

Active Member
Messages
43
Location
Grand Rapids, MI
Thanks for posting the wiring diagram, that simplifies things a bit.

I am not super familiar with reading these but to me it looks like Orange is 12 volt + and pink/blue are the switched grounds.

I do plan to incorporate a relay but I have never used one for something that isn't + switched.

I am guessing I use the pink as my -12 volt trigger wire.

Am I completly wrong?
 

JPaul

Well-Known Member
Messages
2,436
Location
Way up north, UT
I[OIIIIIIIO]I;230262 said:
Thanks for posting the wiring diagram, that simplifies things a bit.

I am not super familiar with reading these but to me it looks like Orange is 12 volt + and pink/blue are the switched grounds.

I do plan to incorporate a relay but I have never used one for something that isn't + switched.

I am guessing I use the pink as my -12 volt trigger wire.

Am I completly wrong?

You are correct with how you are reading the color coding, orange is +12v and pink/blue/black is ground (-12v).

It's pretty simple really, instead of having the switch for your relay on the positive side of the relay's coil, you have it on the negative side. Doesn't matter which side of the coil the switch is on, it will work the same regardless. The only difference is when you NEED it to be a positive signal for whatever you are tying in, like something that is electronically switched (though if you are rolling your own circuit you can get components that accept a negative signal instead of a positive signal, but I digress).

So when wiring in the relay just run a positive wire with a fuse from the battery or an add-a-fuse or whatever to the positive side of the relay coil, then connect the negative side of the relay coil to the headlight harness on the blue or pink wire. I have no idea which one is for low vs high so you'll need to test that to confirm. To test it you turn on your low beams and then you should be able to disconnect one of the bulbs, put a meter that is set to Ohm's between the bulb socket terminal for the blue or pink wire and any ground to see if the circuit is closed.



The other option you have is if you have your driving lights completely separate from the factory lighting, is to just tap into the orange wire to power the switch for your driving lights, then the switch controls the relay for the driving lights. This way the driving lights can be on whether the low or high beams are on, but will turn off if the headlights are off completely. So orange wire to switch, switch to relay coil +12v, relay coil -12v to ground.

Or just hook the switch to a wire that is powered when the ignition is on so that you can have your driving lights on no matter if the headlights are on or not.
 

I[OIIIIIIIO]I

Active Member
Messages
43
Location
Grand Rapids, MI
Thanks for the replies, I finally had time to install and wire up my lights!

I did have one issue i am working out still.

here a a couple pics.....


20190403_101512.jpg

20190403_101435.jpg
 
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I[OIIIIIIIO]I

Active Member
Messages
43
Location
Grand Rapids, MI
Like I said, there is one minor issue.....

I wired up my relay for the new lights using the hi beam headlights negative wire as my trigger.

Everything works perfectly and they come on with the hi beams exactly the way i want and they are super bright!:)




However there is a problem.....when I shut the car off both headlights remain lit very dimly (they are LED) even less bright than the DRL lights. They stay lit even with the key off. The only way to shut them off is to remove the negative trigger wire.:gaah:



Temporarily, to fix the issue, I just wired another relay in that is ignition switched so everything shuts off now with the key.

This seems to work fine for but I don't want any long term issues from this.

I swapped the relay to make sure it wasn't defective and the new one did the same thing.

I did some quick research online and it sounds like I may have an issue with "backfeed" through the relay. The recommended fix is to install a diode to eliminate the issue. This is all new territory for me. I am going to order a diode and see if that fixes it.

Any thoughts on this or experience using diodes to fix it???
 
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jakesz28

Well-Known Member
Messages
1,056
Location
Cabool MO
There is a good right up on doing that in here. Dont have time right now, may look for it later. Google it here or try the search.
 
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