Headlight high-beam splice point

[bobholthaus]

Okay, makes sense now, I understand that Busbar. Great idea to use that, I don’t know why Jeep doesn’t just give us one of those at the end of all the OEM wiring.

I’m not sure I can explain all this in a thread, but I’ll try. Right now, you have 12 V flowing from the battery, through the auxiliary switch, to the bus bar, and ultimately to the lights (you have relays in there, too?). So just imagine that the battery is like the source of water and it is literally flowing in that direction to your lights.

When you tap the highbeam to have a second trigger, it’s like a second source of water in the analogy. So, if you eliminated the auxiliary switch, you could have the wire come from your highbeam trigger to your bus Barr to your relay and then to the lights and every time your highbeams went on that trigger is acting exactly like the power that flows through the aux switch. Does that make sense?

So the challenge you’re facing is you want to be able to trigger the lights on with your aux switch while potentially having them go on with your highbeams, and this is a functional limitation of the aux switches, because they cannot be wired with two sources (one being the battery, the other being the trigger from the high beams).

And at this point, it’s way too much to put in this thread on what your functional options are. Give me a call and I’ll be happy to walk through it with you. There may be guys that can tell you how to rewire the aux switch altogether, but I don’t think you’re going to be able to use it exactly the way you want to potentially in regards to the highbeams, but let’s talk when you get a chance. I’ll be happy to walk you through it.

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[bobholthaus]

The simple punchline is this: you can use the aux button like you are today, turning the lights on and off. You can also have the lights come on with the highbeams, but you cannot have the aux switch override that functionality, meaning every time your highbeams went on, the lights would come on regardless of whether that switch was on or off. If that’s OK (meaning you cannot override the “lights on with high beams”), then using your existing relay and a diode I is a simple wiring add to make it work.

What you really need is a three-way switch, where in position one the lights would be on; in position two the lights would be off; and in position three the lights would come on with your highbeams. Unfortunately, the OEM aux switches are not set up for this at all. This is where having something like a Switch-Pros or a competitor is really helpful because they are designed to be able to use this “three-way” functionality built right into the system. Or, you can add some other kind of switch in your cab to be able to override this (I’ll explain this).

Although, I will caveat these comments with the fact that I’m sure there is someone else who has figured out a way to use two of their Aux switches to do what I am talking about. And if I think about it long enough, I may be able to figure it out as well.

 

[Grayhound]

I think I’m following what your saying. Let me pose the question this way: if I had the switch run to a relay that had the battery side hooked up to the high beam trigger wire and then that fed the normal relay I have to the battery and lights would that create a scenario where I could have the aux button on but the light would not come on until I hit the high beams? Then I could trigger on the lights I want to be working with the high beams via the aux switch?

 

[bobholthaus]

I think I’m following what your saying. Let me pose the question this way: if I had the switch run to a relay that had the battery side hooked up to the high beam trigger wire and then that fed the normal relay I have to the battery and lights would that create a scenario where I could have the aux button on but the light would not come on until I hit the high beams? Then I could trigger on the lights I want to be working with the high beams via the aux switch?

yes, you are following it correctly. That scenario would work but in that case the lights would only go on when you have the switch turned on and the highbeams triggered.

So, your second relay is turned on/off by the Aux switch, and it’s positive feed IS your wire from your high beam tap, flowing through that relay to the main relay powering the lights (which then becomes the one/off of that relay).

and now, it just came to my mind how you could use a different Aux switch to power the lights on off. If…. Have edited this three times and it keeps glitching.

 

[bobholthaus]

If you put a diode on the wire running from the second relay to the main relay, the power can’t back feed to that relay.

Then you could run a wire from a second Aux switch to your main relay, and put a diode on that wire as well. Then your second Aux switch can be an independent on/off.

In that scenario, you could use your first Aux switch as your trigger for the highbeams, while using a second Aux switch to manually turn the lights on and off. Does that make sense?

If you need a very simple diode set up, Waytek Wire makes a plug-in play diode that plugs in like a mini fuse and makes wiring very simple. I’m not at my house so I can’t send you a picture of that, but I’m happy to share part numbers with you tomorrow if needed.

Nice work on the introduction of the second relay to make it all work.

 

[THAW]

If you put a diode on the wire running from the second relay to the main relay, the power can’t back feed to that relay.

Then you could run a wire from a second Aux switch to your main relay, and put a diode on that wire as well. Then your second Aux switch can be an independent on/off.

In that scenario, you could use your first Aux switch as your trigger for the highbeams, while using a second Aux switch to manually turn the lights on and off. Does that make sense?

If you need a very simple diode set up, Waytek Wire makes a plug-in play diode that plugs in like a mini fuse and makes wiring very simple. I’m not at my house so I can’t send you a picture of that, but I’m happy to share part numbers with you tomorrow if needed.

Nice work on the introduction of the second relay to make it all work.

Perhaps I misunderstand @Grayhound's goal, but...

Just run the aux switch wire to the load (lights) and back to ground. Attach the power side of a relay along that powered aux switch wire or ground wire path. Attach the tapped high beam to the switch side of the relay and ground the other side of the relay's switch.

Then do the same for the other aux switch and load.

Two relays, and no diodes required. The high beams and the aux switch both have to be on for the load to be on. If the high beams are on, the aux switches turn their load on/off. If an aux switch is on, the high beams switch its load on/off.

 

[bobholthaus]

Perhaps I misunderstand @Greyhound's goal, but...

Just run the aux switch wire to the load (lights) and back to ground. Attach the power side of a relay along that powered aux switch wire or ground wire path. Attach the tapped high beam to the switch side of the relay and ground the other side of the relay's switch.

Then do the same for the other aux switch and load.

Two relays, and no diodes required. The high beams and the aux switch both have to be on for the load to be on. If the high beams are on, the aux switches turn their load on/off. If an aux switch is on, the high beams switch its load on/off.

I’ve read this 3 times and I don’t follow you THAW (although it’s not me that needs to understand it, ha!) if you can eliminate a diode and keep 2 relays, then it’s worth some clarity, please. I love to understand this stuff.

 

[bobholthaus]

Perhaps I misunderstand @Greyhound's goal, but...

Just run the aux switch wire to the load (lights) and back to ground. Attach the power side of a relay along that powered aux switch wire or ground wire path. Attach the tapped high beam to the switch side of the relay and ground the other side of the relay's switch.

Then do the same for the other aux switch and load.

Two relays, and no diodes required. The high beams and the aux switch both have to be on for the load to be on. If the high beams are on, the aux switches turn their load on/off. If an aux switch is on, the high beams switch its load on/off.

Wait, I think you’re saying both the high beams AND the aux switches need to be on. In my example, one Aux switch toggles the lights on and off WHEN the high beams are on, and the other Aux switch is a manual on/off. In my example, you can either have the high beams turn them on, OR you can manually turn them on and off. The best of both worlds.

if your setup does the same thing, I apologize for not understanding.

 

[AFD]

Wait, I think you’re saying both the high beams AND the aux switches need to be on. In my example, one Aux switch toggles the lights on and off WHEN the high beams are on, and the other Aux switch is a manual on/off. In my example, you can either have the high beams turn them on, OR you can manually turn them on and off. The best of both worlds.

if your setup does the same thing, I apologize for not understanding.

Yes, I think he's saying the AUX switch must be on (allowing power to the light) while the highbeam also needs to be on (and connected to the relay). Think this is the simplest to wire and also allows "auxiliary driving lights" to adhere to some state laws.

 

[THAW]

Wait, I think you’re saying both the high beams AND the aux switches need to be on. In my example, one Aux switch toggles the lights on and off WHEN the high beams are on, and the other Aux switch is a manual on/off. In my example, you can either have the high beams turn them on, OR you can manually turn them on and off. The best of both worlds.

if your setup does the same thing, I apologize for not understanding.

My interpretation is the "manual" switch wasn't requested in the original post.

If that's part of the design, use a 5 pin relay and attach the "manual" aux switch wire to the normally closed pin.

 

[THAW]

I’ve read this 3 times and I don’t follow you THAW (although it’s not me that needs to understand it, ha!) if you can eliminate a diode and keep 2 relays, then it’s worth some clarity, please. I love to understand this stuff.

I attempted to be as clear and concise as possible. Based on your latest post, it appears you understand my wiring suggestion ?. But if you need more clarity let me know which parts are confusing.

One thing that may be unclear is the number of relays. Only 1 relay is needed per load. the reason I stated a requirement for 2 relays is the original post mentioned 2 sets of lights.

 

[THAW]

If you put a diode on the wire running from the second relay to the main relay, the power can’t back feed to that relay.

Then you could run a wire from a second Aux switch to your main relay, and put a diode on that wire as well. Then your second Aux switch can be an independent on/off.

In that scenario, you could use your first Aux switch as your trigger for the highbeams, while using a second Aux switch to manually turn the lights on and off. Does that make sense?

If you need a very simple diode set up, Waytek Wire makes a plug-in play diode that plugs in like a mini fuse and makes wiring very simple. I’m not at my house so I can’t send you a picture of that, but I’m happy to share part numbers with you tomorrow if needed.

Nice work on the introduction of the second relay to make it all work.

I firmly believe you can (and should) achieve all the functional requirements without the complexity of diodes.

However, if you do go the diode route, be aware that to avoid overheating/fire risk any wires downstream of the separately powered connected wires need to be sized for the combined fuse rating.

 

[bobholthaus]

My interpretation is the "manual" switch wasn't requested in the original post.

If that's part of the design, use a 5 pin relay and attach the "manual" aux switch wire to the normally closed pin.

Finally got a chance to focus on this, THAW. I finally see that your idea is to run the Aux wiring to pin 30 on a traditional relay (where it is the feed of 12V to the relay for powering purposes). Pin 85, the low volt input, is from the high beam trigger. Pin 87 goes to the lights. Therefore, Aux switch being on does nothing unless the high beams "trigger" the relay on. Nice.

Can you please explain to me how you'd use a second Aux switch wiring to the 5th pin on a relay (would that be 87A (which power flows through when the relay is off))? This part I am really confused on, but I really want to learn how you could use a single relay to accomplish both scenarios:

1. High Beams on, Aux switch #1 on, lights on (accomplished in your explanation)
2. Aux Switch #2 on, lights on (using the 5th pin of the relay)

Thanks!

 

[THAW]

Finally got a chance to focus on this, THAW. I finally see that your idea is to run the Aux wiring to pin 30 on a traditional relay (where it is the feed of 12V to the relay for powering purposes). Pin 85, the low volt input, is from the high beam trigger. Pin 87 goes to the lights. Therefore, Aux switch being on does nothing unless the high beams "trigger" the relay on. Nice.

Can you please explain to me how you'd use a second Aux switch wiring to the 5th pin on a relay (would that be 87A (which power flows through when the relay is off))? This part I am really confused on, but I really want to learn how you could use a single relay to accomplish both scenarios:

1. High Beams on, Aux switch #1 on, lights on (accomplished in your explanation)
2. Aux Switch #2 on, lights on (using the 5th pin of the relay)

Thanks!

You've got the first part right, that was my original suggestion.

To use the second aux switch for what you earlier called the "manual" switch, start by reversing pins 30 and 87. So, the first powered aux switch wire to 87, and 30 to the load (aux lights). Then connect the ("manual") second powered aux switch wire to pin 87A.

The high beams will effectively switch which aux switch turns on the load (aux lights).

This wiring configuration has one minor difference from yours (assuming I understand yours correctly): the "manual" second aux switch is bypassed when the high beams are engaged. That variation might give the appearance of not meeting your requirements, but all the same functionality exists; either use the "manual" switch only when the high beams won't be engaged, or think of the "manual" switch as both aux switches together, and everything works exactly the way you want. Put another way, this configuration adds the ability to turn off (not just on) a load when the high beams are engaged.

To map it to your 3 position switch:
pos1, aux lights on = both aux buttons on (or aux 1 off if high beams won't be engaged + aux2 on)
pos2, aux lights off = both aux buttons off
pos3, aux lights controlled by high beams = aux 1 on + aux 2 off
[extra pos4, aux lights reverse controlled by high beams = aux 1 off + aux 2 on]

All using a single 5-pin relay and no diodes.

 

[bobholthaus]

You've got the first part right, that was my original suggestion.

To use the second aux switch for what you earlier called the "manual" switch, start by reversing pins 30 and 87. So, the first powered aux switch wire to 87, and 30 to the load (aux lights). Then connect the ("manual") second powered aux switch wire to pin 87A.

The high beams will effectively switch which aux switch turns on the load (aux lights).

This wiring configuration has one minor difference from yours (assuming I understand yours correctly): the "manual" second aux switch is bypassed when the high beams are engaged. That variation might give the appearance of not meeting your requirements, but all the same functionality exists; either use the "manual" switch only when the high beams won't be engaged, or think of the "manual" switch as both aux switches together, and everything works exactly the way you want. Put another way, this configuration adds the ability to turn off (not just on) a load when the high beams are engaged.

To map it to your 3 position switch:
pos1, aux lights on = both aux buttons on (or aux 1 off if high beams won't be engaged + aux2 on)
pos2, aux lights off = both aux buttons off
pos3, aux lights controlled by high beams = aux 1 on + aux 2 off
[extra pos4, aux lights reverse controlled by high beams = aux 1 off + aux 2 on]

All using a single 5-pin relay and no diodes.

Brilliant! It makes total sense to me, now that you explain the power flowing from 87/87a TO 30. My mind wasn’t registering that properly. So a 5 pin relay can act like a 3 position switch. No diodes needed.

Any chance you’d draw a schematic for those who don’t understand this? If not, I will when I have time. Thanks again.

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