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Schematic or high beam trigger for lights?

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Old Mar 9, 2017 | 06:52 PM
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Question Schematic or high beam trigger for lights?

If anyone could provide info on where to tap into the high beam hot to use as a trigger for the relay on my spots I would greatly appreciate it. I could obviously do it at the headlight but would much prefer to do it at the box. (NOT the passenger compartment fuse box, the one in the engine compartment.) Many people must have done this, right? I wish that manufacturers wouldn't relegate a simple freaking schematic as some sort of holy grail. It's like a state secret or something. They don't even include a full chassis wiring schematic for cab/chassis upfitters on their owner site. This should be included as very basic and necessary information for anyone who drops too much money on a pickup. (Not that it wasn't money well spent on this most awesome truck.) Jeez, Louise!
 
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Old Mar 9, 2017 | 07:31 PM
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Off topic, but those wheels look great on your truck!

Back on topic....not only do you need the correct wire, but you'll want to make sure it is 12 volts.
 
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Old Mar 9, 2017 | 09:06 PM
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Got complete schematic for my 2017 F350 at Helm Inc $81
 
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Old Mar 9, 2017 | 09:24 PM
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Do you have the upfitter switches? For what it's worth, I would directly wire hot to the lights on up fitters and not touch the wiring harness. Especially if you have auto high beam and LED lights. I know that's not necessarily possible on the Supercab, but just saying, I have always done direct wiring via up fitters, and not used the trigger wire. This way you can use as work lights and separately from headlights if ever needed.
 
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Old Mar 9, 2017 | 11:12 PM
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Originally Posted by lkbrow1
Got complete schematic for my 2017 F350 at Helm Inc $81
What a great find.
 
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Old Mar 10, 2017 | 04:43 AM
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In the schematic for the Upfitter relay box is a note that shows a Fuse at F4C and F4A.
Only ONE fuse may be installed. The default is F4A which powers Upfitter switches 5 & 6 in RUN or START. Change the Fuse from F4A to F4C and Upfitter switches 5 & 6 will be powered ALL the time.
 
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Old Mar 10, 2017 | 06:48 AM
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Originally Posted by mhoefer
Do you have the upfitter switches? For what it's worth, I would directly wire hot to the lights on up fitters and not touch the wiring harness. Especially if you have auto high beam and LED lights. I know that's not necessarily possible on the Supercab, but just saying, I have always done direct wiring via up fitters, and not used the trigger wire. This way you can use as work lights and separately from headlights if ever needed.
I am using the upfitter switches as well. I want it triggered by the high beam with the added ability to switch them off completely. Nobody knows where this wire is? Hard to imagine that it's always been done at the headlight with some crappy scotch-lock connector.
 
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Old Mar 10, 2017 | 06:51 AM
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Originally Posted by lkbrow1
In the schematic for the Upfitter relay box is a note that shows a Fuse at F4C and F4A.
Only ONE fuse may be installed. The default is F4A which powers Upfitter switches 5 & 6 in RUN or START. Change the Fuse from F4A to F4C and Upfitter switches 5 & 6 will be powered ALL the time.
Don't need the upfitter info. I'm familiar with it, as with the pass through wires. I need a high beam trigger for my relay, not instructions on how to wire them. I need to know where and how to identify the 12v high beam hot wire where it exits the box on the main harness.
 
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Old Mar 10, 2017 | 06:58 AM
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Thanks.

Originally Posted by klassic
What's a great find.
Thanks, I hadn't found this. I'll check it out. Hopefully I can buy and download and not wait for a disk. Thanks again! 👍🏼
 
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Old Mar 10, 2017 | 07:00 AM
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Originally Posted by lkbrow1
Got complete schematic for my 2017 F350 at Helm Inc $81
Feel like giving it a look? I would appreciate it. It's probably the only time I'll ever have to use a full schematic.
 
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Old Mar 10, 2017 | 07:13 AM
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The High Beam wire comes out of the Body Control Module on Pin 11 on a GY-BN wire.
A micro controls this wire so there is nothing upstream to connect to. There are separate wires for each headlight with some types of Headlights, but it appears like 11 is common to all of them.
 
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Old Mar 10, 2017 | 07:27 AM
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Holy smoke. PAPER?!?! REALLY?!?!

Originally Posted by lkbrow1
Got complete schematic for my 2017 F350 at Helm Inc $81
I ordered it. I'm getting PAPER schematics! Isn't that the thin, white leafy stuff made out of trees? Really surprising that this isn't available in any digital format whatsoever. The shop manual is available for $177.00 on CD but only includes partial schematics. The multi year collection is available on DVD for over $2K (!!) but you MUST buy the wiring diagram in paper. Strange. At least it was available. And thanks for the tip.
 
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Old Mar 10, 2017 | 07:50 AM
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Outstanding!

Originally Posted by lkbrow1
The High Beam wire comes out of the Body Control Module on Pin 11 on a GY-BN wire.
A micro controls this wire so there is nothing upstream to connect to. There are separate wires for each headlight with some types of Headlights, but it appears like 11 is common to all of them.
Wow, thanks so much! I'll be able to do this trigger wire this morning while waiting for my paper schematic in the snail mail. And just to clarify, that's grey /brown from pin 11? Does it suggest it's 12 volt? If not I'll test it. MAJOR help.
 
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Old Mar 10, 2017 | 07:54 AM
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Originally Posted by lkbrow1
There are separate wires for each headlight with some types of Headlights, but it appears like 11 is common to all of them.
That makes sense. If you had the auto-dim it would be switched upstream of that at the PCM. Perfect.
 
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Old Mar 10, 2017 | 06:15 PM
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The power goes through a FET so it can go on and off gradually. But it is a 12 volt circuit.
 
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