I've gotten a million pm's from people asking how exactly to do this modification. I enjoy helping others out so I'm putting together this thread as a how to. Mind you, this is for an 03 model year on up to 07. The new body style's are different.
Parts needed.
Diodes from Radio Shack. Part #'s 4001, 4002, 4003, or 4004. They're all basically the same and your only issue is gonna be the length. They're less than a dollar so its relatively cheap...
Everything runs from the low beam fuse. The low beam fuse has 4 pins, labeled with numbers. Take the 85 pin and run the diode with the bottle cap pointing toward the highbeam fuse 85 pin. You have to pull out the fuse and look at the numbers to make sure you're getting the right one.
After running the diode from the low to the high beam 85 pin, you now will be able to reain your low beams with the use of your highbeams.
Next, take the second diode and run it from the 85 pin of the low beam fuse and connect it to the 85 leg of the fog light fuse. You can wrap the diode around the leg itself, stick it in the hole or solder it, its up to you. Soldering it obviously is the best option since its gonna be a fail safe connection. Once they're connected to the 85 pins, you now will retain your fog lights with the use of your high beams as well.
Or....
You can take the diode and run it from the 85 pin of the highbeams and connect it to the 85 pin of the fog lights. Now you'll be able to retain your fog lights, when your low beams are on.
Some people use the DRL's as well. Some people may think that this could overload the circut. I opted not to use my DRL's because they dont put out much light anyways and I didnt want to fry anything.
As always, if you get lost, pm me and I'll walk you through it over the phone.
Also install a switch. That way you can disable this deal. Most plow lights run a high/low bulb and I doubt it would be happy running both filaments in the same bulb at the same time. Or just dont ever use your high beams when the headgear is attached......
JK. Actually I was going to look into if the 06 and my 03 were the same and would work. Since you did this on your LBZ I'd say I am safe
With this set up can you run the low beams only? I have both diodes coming off the high beam relay that way I still get all on, activated by the high beams. Then the options of low beam only, low beam plus fog with the switch on the dash, and fog only.
Unit, what size are these diodes? It seems Radio Shack no longer has stores in Canada, so I guess I need to grab them elsewhere.
You guys say you're "playing" around trying to find what works. How much damage can one do by playing around with different combos of diodes? I basically want to achieve all headlights on when I flip the toggle activating the high beams so then the lows would just stay on. I'd preferably like to have separate control over the fogs if it's possible.
Unit, what size are these diodes? It seems Radio Shack no longer has stores in Canada, so I guess I need to grab them elsewhere.
You guys say you're "playing" around trying to find what works. How much damage can one do by playing around with different combos of diodes? I basically want to achieve all headlights on when I flip the toggle activating the high beams so then the lows would just stay on. I'd preferably like to have separate control over the fogs if it's possible.
Check with an electronics component supplier like Mouser. The actual diode p/n is 1N4001, 1N4002, etc... You may be held to a minimum order quantity or $$ going through one of those places if Radio Shack doesn't have them.
Im not kidding. I hate the cycle of the lights turning on while Im waiting for my glow plugs to warm up. On/off/on is not good for HID's so I wanted to either to put a timer to be able to turn my lights on later, like 30 seconds after start up, or simply disable it.
I wait for the plugs because in the winter time, we have a couple months on end when its BELOW zero....Not much warms up fast in sub zero temps.
I went through it last winter when the truck was brand new.
And yes, I can adjust the lights, but you have to turn the controls, at the right second, when turning the key to the on position for the glow plugs. Its a 50/50 chance that they wont come on. PITA....Strip the wires to the sensor, run a jumper, problem solved.
I wait for the plugs because in the winter time, we have a couple months on end when its BELOW zero....Not much warms up fast in sub zero temps.
I went through it last winter when the truck was brand new.
And yes, I can adjust the lights, but you have to turn the controls, at the right second, when turning the key to the on position for the glow plugs. Its a 50/50 chance that they wont come on. PITA....Strip the wires to the sensor, run a jumper, problem solved.
Hey Nick - I have the same feature in my Canadian truck .... so you ran a jumper between the two wires on the small round dash sensor to defeat the auto lights ?? Did you still leave the wires connected to the sensor ?
I've tried it a few ways with the diodes. When my low beams are on, my fogs are on. Its a one packahe deal. You can however just hit your fog light button and not get your low beams as well.
if you use the diode to link the fog light fuse to the low beam light fuse then whenever you turn on your low beams your fogs will automatically come on also. when you turn your highs on then you will have all three on. you will never have to use your fog light button.
if you use the diode to link the fog light fuse to the low beam light fuse then whenever you turn on your low beams your fogs will automatically come on also. when you turn your highs on then you will have all three on. you will never have to use your fog light button.
If you only link the lows to the highs via diode your fog should work like they do normally...Its only when you link those via diode as well that they all 6 come on...
The problem with that though is that whenever you hit your highs, while your lows will stay on with the highs, you'll lose your fogs as result of the BCM and the way its coded. With the config/work around we're discussing this mod enables:
Low= low w/option of fogs
High= highs, lows, and fogs.
Maybe someone else can chime in with a mod to the mod for what your asking about. IMO, you probably have to wire in another switch....
Maybe I did something wrong then because I have no control of the fogs when my low beams are on. Its a 1 package deal.
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