Ok, so "best" might be a stretch...
I think it's the easiest, least invasive and cheapest way to do it
I took this off my truck to show y'all this, so I dont have a "start to finish" pic stream....
Here's how I did it though...
This is another alternative to the all on mod that I've seen others take, and a way less expensive and less invasive option than wiring in a separate harness and fuse, and you don't cut into or splice anything. This is an option that takes about 10min to do and costs $3 or less and can be done in the top of the fuse box...
You just need to tie a diode in line between the # 85 pins on the relay fuses for the head/fog/brights, at least that's the pin # that works on 06-10 trucks.
Just run one diode off of each the head and fog lights #85 pin of the gray square relay fuse in the under hood fuse box.
The diode type you'll need or diode # is 4004, I got them from radio shack, you will need only two, they come in a pack of 3 iirc, buy two packs....
there's actually a couple threads about it here...completing the task in a similar fashion...
Here's a pic of the fuse diagram, I circled the #85 pin locations and drew with a red line the path I took, each black square thingy in the red line is a diode, this was an old path, I realized I only needed two diodes after a couple attempts...
To do this you will need to use two #4004 diodes, making sure to always have the grey band on the diode facing the high beam relay, take one diode full length from the low beam relay #85 pin, to the high beam relay #85 pin bend it to fit between the fuses and make sure it is centered leaving equal amount of diode wire on each side, on the low beam side, using as little length as possible, make the diode wire bend all the way around the 85 pin to secure it in place, I used needle nose pliers to do this to keep the diode wire neat and tight to the pin. After the circlet has been completed, refit the diode with it attached to the low beam relay and set the relay in place, now, making sure the diode fits between both the high and low beam relays, bend a "leg" on the diode wire on the high beam relay side to set it into the the #85 pin location of the fuse panel and set the leg into that hole, then set the high beam relay, it should secure the diode wire in the receptacle.
Now, your done if all you want to do is run the high and low beams together...
If you have, and would also like to run and keep your fog lights on for the "6 HI mod", you need to run another diode from the #85 pin of the fog relay, with the grey band of the diode on the high beam side of the circuit, make a leg to drop into the 85 pin slot for the fog light relay, set the leg into the hole and fit the fog diode to the hi/lo diode you preciously set, cut the fog diode wire in front of the diode to fit with, and solder it to the hi/lo diode in front of or on the high beam relay side of the actual diode for the hi/lo path(see pics). Bam, you're done. And it should look something like this, if not better...
With it wired like this the lows and fogs don't ever go off when the high beam circuit is engaged and when you flash your high beams with the light circuit off all the lights will illuminate as well, FYI
I have done this to 3 GM rigs now with no issues
Even though you only need 2 diodes, buy many more, if you try and get everything working and don't have the diodes going the right way, they get fried instantly when you turn the light switch on :thumb:
I think it's the easiest, least invasive and cheapest way to do it
I took this off my truck to show y'all this, so I dont have a "start to finish" pic stream....
Here's how I did it though...
This is another alternative to the all on mod that I've seen others take, and a way less expensive and less invasive option than wiring in a separate harness and fuse, and you don't cut into or splice anything. This is an option that takes about 10min to do and costs $3 or less and can be done in the top of the fuse box...
You just need to tie a diode in line between the # 85 pins on the relay fuses for the head/fog/brights, at least that's the pin # that works on 06-10 trucks.
Just run one diode off of each the head and fog lights #85 pin of the gray square relay fuse in the under hood fuse box.
The diode type you'll need or diode # is 4004, I got them from radio shack, you will need only two, they come in a pack of 3 iirc, buy two packs....
there's actually a couple threads about it here...completing the task in a similar fashion...
Here's a pic of the fuse diagram, I circled the #85 pin locations and drew with a red line the path I took, each black square thingy in the red line is a diode, this was an old path, I realized I only needed two diodes after a couple attempts...
To do this you will need to use two #4004 diodes, making sure to always have the grey band on the diode facing the high beam relay, take one diode full length from the low beam relay #85 pin, to the high beam relay #85 pin bend it to fit between the fuses and make sure it is centered leaving equal amount of diode wire on each side, on the low beam side, using as little length as possible, make the diode wire bend all the way around the 85 pin to secure it in place, I used needle nose pliers to do this to keep the diode wire neat and tight to the pin. After the circlet has been completed, refit the diode with it attached to the low beam relay and set the relay in place, now, making sure the diode fits between both the high and low beam relays, bend a "leg" on the diode wire on the high beam relay side to set it into the the #85 pin location of the fuse panel and set the leg into that hole, then set the high beam relay, it should secure the diode wire in the receptacle.
Now, your done if all you want to do is run the high and low beams together...
If you have, and would also like to run and keep your fog lights on for the "6 HI mod", you need to run another diode from the #85 pin of the fog relay, with the grey band of the diode on the high beam side of the circuit, make a leg to drop into the 85 pin slot for the fog light relay, set the leg into the hole and fit the fog diode to the hi/lo diode you preciously set, cut the fog diode wire in front of the diode to fit with, and solder it to the hi/lo diode in front of or on the high beam relay side of the actual diode for the hi/lo path(see pics). Bam, you're done. And it should look something like this, if not better...
With it wired like this the lows and fogs don't ever go off when the high beam circuit is engaged and when you flash your high beams with the light circuit off all the lights will illuminate as well, FYI
I have done this to 3 GM rigs now with no issues
Even though you only need 2 diodes, buy many more, if you try and get everything working and don't have the diodes going the right way, they get fried instantly when you turn the light switch on :thumb:
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and I've done it several times, and ran this set up like this for years
