Tech: Quad beam headlight mod

Rollin Thunder

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Once the diode is in place, the neg current from the BCM's high beam signal wire will also trigger the signal wire for the low beams. These wires close the contacts on their respective relays, powering up the lights.

ok COOL. so it wont over load the high beams and blow somthing up. :sla:

o yea, i just installed 100 watt offroad halagons, do you think thats gunna mess up somthing when i do this mod??

now are there two wires i can put another diode to keep the fogs on??? :cool:


this thred should be a sticky.
 
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road1will

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ya, the point of the diode is to switch the lows on every time the highs are switched on, but not to switch the highs on any time the lows are on.

i think jk said you can just jumper the fog switch right behind the light switch panel.
 

Rollin Thunder

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ya, the point of the diode is to switch the lows on every time the highs are switched on, but not to switch the highs on any time the lows are on.

i think jk said you can just jumper the fog switch right behind the light switch panel.

JUMPER???? :skep: :umn: :ktoe: :confused: :confused:
 

Brandon00hoe

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Ok on this fog light mod. What wires do I need to jump? There are alot of wires behind the switches and I don't want mess anything up.
 

JKmotorsports

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Ok on this fog light mod. What wires do I need to jump? There are alot of wires behind the switches and I don't want mess anything up.
Make sure you test these wires first because I'm running off memory right now.
Behind the parking/headlight switch, test the lt blue wire for power when you turn the parking lights on. You want the wire that switches on/off when you switch the parking lights. I mentioned to test the lt blue one because I think this is the one. If not just go down the line till you get the right wire. On the fog light switch , test the black, orange, and purple wire. You want the wire that switches on/off when you push the fog light button. When you find the two wires you need, use a piece of jumper wire (14-18 gauge) to connect the two wires. This should get your fogs to come on with the parking lights and stay on when you switch to high beams.
 

Brandon00hoe

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Jk, You've got a damn good memory. I just did it and on mine behind the headlight switch its the LT Blue for parking and Yellow for headlights. On the fog switch its the Purple. I hooked it up to come on with the headlight. Works great on the lights come and no problems. Thanks again JK for saving the day!
 

madspeed

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For 10 years, I ran either 100/80 watt bulbs or 130/100 watt bulbs in my Wing. I made uncounted runs in endurance rallies where the lights were never turned off for up to 24 hours at a time. I even tested to see if the wires got hot. In 10 years of running those bulbs, the wires never even got warm to the touch, and the lamp housings never melted or degraded in any way. (I did not continue to use 130/100 bulbs because the wiring could not supply the current they needed for full brightness, without installing larger wires and relays. Call me lazy!)
can you recommend any 80/100's that can be found on the net/
 

schuck

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You say to locate the BCM. Ok, I'm new, what is the BCM? Next, what size/type of diode do you need to buy?

Thanks!!!
Steve
 

FergHoe

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All that is is a relay. You can go to the autoparts store and spend alot less than 15.00. looks like there is still some wiring needed with that "kit".
 

D'Hag

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You say to locate the BCM. Ok, I'm new, what is the BCM? Next, what size/type of diode do you need to buy?

Thanks!!!
Steve

To all who are interested, in my '03 I found a MUCH easier way to do this. I think this should work for 2003 and newer models.

First, go to Radio Shack and buy any good 1-3 amp rectifier diode. Cost is about 3 bucks for a pair. The total length of these diodes are about 3 inches between the ends of the leads. That's long enough.

Go into the engine compartment and locate the fuse/relay box. In my '03, it's on the driver side. In there, locate the two headlight relays. There is one for high beam and one for low beam. Make note of the direction they are installed, and pull them out. You will see there are four holes that each relay plugs into, in a rectangular pattern.

The lights are switched when something (the dimmer switch or the BCM-- Don't know-- Don't care.) grounds the relay trigger. When you stand beside the truck on the driver's side, facing the fender, the trigger ground is the LOWER RIGHT hole of each relay socket.

Lay a diode between the LOWER RIGHT hole of the high beam relay socket and the LOWER RIGHT hole of the low beam relay socket. (If you know how to read the markings on a diode, you want current to flow from the low beam socket to the high beam socket.) Bend the leads so they will not short near any other holes. Bend the very ends of the leads to extend into the LOWER RIGHT holes of the relay sockets.

Don't try to push the leads down into the sockets. They won't go. All you're after is to get the ends of the leads where they will solidly contact the relay pins when you put the relays back in.

Put the relays back in their sockets. Be sure they are right-side up, and that the leads of the diode make good contact with the leads on the relays. The relay pins should pinch the diode leads against the plastic of the socket, making a solid connection.

Test the lights. If you get all four lamps when you switch to low beam, reverse the diode.

Pictures--
1. The fuse/relay box.
2. The headlamp relays (red arrows). High beam is the upper left, low beam is lower right.
3. How to lay the diode in place (red arrow). Note the gray bar on the diode is toward the high beam socket.
4. The final installation. Diode is marked by the red arrow.
 

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Rollin Thunder

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To all who are interested, in my '03 I found a MUCH easier way to do this. I think this should work for 2003 and newer models.

First, go to Radio Shack and buy any good 1-3 amp rectifier diode. Cost is about 3 bucks for a pair. The total length of these diodes are about 3 inches between the ends of the leads. That's long enough.

Go into the engine compartment and locate the fuse/relay box. In my '03, it's on the driver side. In there, locate the two headlight relays. There is one for high beam and one for low beam. Make note of the direction they are installed, and pull them out. You will see there are four holes that each relay plugs into, in a rectangular pattern.

The lights are switched when something (the dimmer switch or the BCM-- Don't know-- Don't care.) grounds the relay trigger. When you stand beside the truck on the driver's side, facing the fender, the trigger ground is the LOWER RIGHT hole of each relay socket.

Lay a diode between the LOWER RIGHT hole of the high beam relay socket and the LOWER RIGHT hole of the low beam relay socket. (If you know how to read the markings on a diode, you want current to flow from the low beam socket to the high beam socket.) Bend the leads so they will not short near any other holes. Bend the very ends of the leads to extend into the LOWER RIGHT holes of the relay sockets.

Don't try to push the leads down into the sockets. They won't go. All you're after is to get the ends of the leads where they will solidly contact the relay pins when you put the relays back in.

Put the relays back in their sockets. Be sure they are right-side up, and that the leads of the diode make good contact with the leads on the relays. The relay pins should pinch the diode leads against the plastic of the socket, making a solid connection.

Test the lights. If you get all four lamps when you switch to low beam, reverse the diode.

Pictures--
1. The fuse/relay box.
2. The headlamp relays (red arrows). High beam is the upper left, low beam is lower right.
3. How to lay the diode in place (red arrow). Note the gray bar on the diode is toward the high beam socket.
4. The final installation. Diode is marked by the red arrow.


just installed my diode this way since the one under my dash kept falling out. works great and took 2 min insted of 20. knock on wood. looks and feels more secure. thanks for telling us this.
 

Rollin Thunder

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i took D HAG's MOD one step further. if you have poor soldering skills like me (my fog jumping failed today) then you can do this.

what i did is got the same diode i used for the lows and highs. (3 amp, 50V resicitifer) and put it on the fog and high beam fuse just like the low and high beam fuse. so when ever my highs are on my fogs are on. but still can be turned on and off when just using lows with the same interior switch. best mod EVER.

bacilly use the same steps D hag has pictured except put a diode in the TOP LEFT CORNER of your FOG fuse. grey band faceing the same way as a low beam. use the chart on your engine fuse box to guide you to the fog.
 
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