How To: Quad Beams and Automatic Fogs

[Regulator]

Quad Beam Headlights / Multifunction Switch Alternate Wiring

The multifunction switch (high beam/directional) signals the Body Control Module (BCM) when the driver turns the high beams (highs only) on or Flash-to-Pass (High and low beams together.) This modification will reverse the signals to the BCM, so that when the high beams are turned on, you have quad beam Headlights. With this mod, Flash-to-Pass will only turn on the high beam lamps; the low beams WILL shut off.

NOTE: This modification requires an alteration to the factory wiring harness connector; improper handling of the connector could result in safety/drivability concerns. Use extreme care and judgment when performing this modification!

Estimated time: 15-30 minutes

Approximate cost: $0 unless purchasing a tool is required

Tools required: 1/4" 7mm socket, 1/4" extension, 1/4" ratchet, pocket screwdriver, terminal connector release tool

Parts and Supplies: None

Step 1) Start by removing the lower cover under the drivers side of the dash board (2-7mm bolts - Red Arrows)

Step 2) Remove the knee bolster cover (4-7mm bolts - Blue Arrows). The knee bolster bolt covers (X2) can be removed using a pocket screw driver to pry them off.

Step 3) Remove the metal knee bolster. (2-10mm bolts - Red Arrows)

Step 4) You will see a large connector with a gold bolt in the center (Red Arrow)...Using a 7mm socket on an extension, unscrew the bolt. When the bolt is loose enough, you will be able to pull the connector apart; pull it out of the steering columns so that you can work on it.

Step 5) Remove row "E" (Red Arrow) from the main body of the connector by placing a flat head screwdriver between the connector and row "E" on the terminal side of the connector. Twist the screw driver and push the wire side of row "E" so it slides away from the connector and separate.

Step 6) Use the pocket screwdriver to press the blue tabs in on the side of row "E" so that the blue "comb" slides out.

Step 7) Look for #11 & #12 on "E" (yellow/black {yellow on older models} wire & light green wire); you will switch these 2 wires using the terminal connector release tool or small eye glass screw driver. Release the terminals as shown. You may need to bend the locking tabs out a bit to make sure they lock back in place.

Step 9) Re-install the blue "comb" into "E". Re-install "E" onto the connector. Re-connect the 2 connector ends and tighten the 7mm bolt.

Step 10) Start the truck and verify modified operation.

Step 11) Install the knee bolster, knee bolster cover and the lower covers.

NOTE: NOT RESPONSIBLE FOR FAILURES CAUSED BY THIS MODIFICATION; WORK PERFORMED AT YOUR OWN RISK!

WARNING: After performing this modification, your (quad) high beam headlights will NOT shut off automatically with the headlight delay. After performing this modification, your "flash-to-pass" switch will only operate with the headlights on.

Fog Light Mod

Step 1) Remove the two phillips head screws (Red Arrows) on the headlight switch panel.

Step 2) Here is where it differs for each vehicle, but you need to get to the wire harnesses behind the switch panel. Hopefully you can figure out how to do it based on your particular model.

Step 3) You will be placing a jumper wire between the pink wire in harness A and the green w/ white stripe wire in harness B. I use wire taps, however the vehicles wiring is thin and you may have to shave some of the insulation off the wire with a razor blade for the taps to make contact.

Step 4) Test all your lights and make sure they are functioning correctly.

Lows with automatically on fogs.

Highs, Lows, and Fogs.

Step 5) Reassemble and enjoy the extra light!

 

[jrSS]

Works flawlessly!! Thanks reg. for hookin me up!! That sure is a sweet truck in the how to pics!!

 

[BO TIE SS]

Thanks to Regulator for putting this article together. I'm just adding information for HID users.
HID users might want to make the following change to keep their lows from going off during "flash to pass" use.

Follow steps #1 - #6 above.

Step 7) Remove only the GREEN wire from #12. Cut off the terminal leaving enough wire attached to the terminal to reconnect later if necessary. Strip 3/4" of insulation off the green wire.

View attachment 18163

Step 8) Remove a small amount of insulation from the yellow/black wire (#11)

View attachment 18164

Step 9) Wrap the green wire around the yellow/black wire. Solder the connection and tape it with electrical tape.

View attachment 18165
View attachment 18166

 

[HARDTRAILZ]

Nice work. I love having my quad beams.

 

[Denis7966]

I wish this thread would have been available 2 years ago when I first got my TB. When I got my TB, the first thing I noticed was that even though I had the high beams on, it didn't seem that much brighter. So I went looking around to see if anything could be done, and I came across a "Trailblazer high beam kit" on e-Bay. So far its worked great for me, but I'm always afraid it might short circuit at some point in the future (I'm paranoid like that).
I think I might just go ahead and remove the kit and reconfigure my lights using this write-up.
Sounds alot safer than an after market solution.

 

[blazinlow89]

I just did the DRL kill mod and quad beams at the same time (same mod lol). I used the relay method, with some wire tapping directly at the BCM. I must say very easy, took my longer than it should have to several set backs such as my DMM not working, and my wire rolls being left at a friends house from this weekend ugh.

The mod worked great but I think I lost my automatic lights, think I just need to drive out of the apartment complex. The HID's look sick, way more output. I got he 6000k from a company on Amazon called Kensun, very impressed. I did manage to plug every harness extension in backwards though, gave me a nice scare when i went to hook the light harness back up.

 

[rppoit]

Ok now my question is, is it safe to do this mod if you already have a DRL killer installed?

 

[jrSS]

Ok now my question is, is it safe to do this mod if you already have a DRL killer installed?

All the quad beam plus fogs mod. does it let's u run all six lights at once. Auto fogs comes on when turning lights on. Drl killer just makes it so u gotta turn lights on manually. So its safe to run both. LOTS of guys with hid's run both of these mods.

 

[Matt]

I run it with mine, with the additional mod that Sam posted, so no matter which way I operate the high beams, the lows don't turn off. I have the DRL Killer from tblazed, so my auto lights still function.

 

[rppoit]

yep just did it and everything is working great so far. And yes my automatic lights work as well. Prob one of the easiest mods ive done thus far. Couldent be happier. Thanks for the write up

 

[andrew4321]

Great write up! Say I only do the fog lamp portion of this mod, will I be able to turn the fogs off using the factory switch? Secondly, I still have my DRL's enabled, will the fogs come on with reduced voltage as the low beams do i.e. will the fogs run as DRL's in concert with the low beam DRL's?

-Andrew

 

[jrSS]

Ur lights will run like normal w/ quad lights +fogs. If u don't wire the auto fogs u just gotta turn on with switch. Light output is the same no matter what.

 

[andrew4321]

Thanks you jrSS for clearing that up for me.

 

[bdorsch44]

THANK YOU! No more driving on winding roads while holding the light stalk in the flash-to-pass position anymore. Myself and my HID's can't thank you enough

 

[tmm217]

Just a quick question. Will doing the quad beam mod work with the DRL capacitor mod? The DRL capacitor mod is to get full voltage to DRL's during daylight. Thanks

 

[jrSS]

To my knowledge yes it should be fine.

 

[Matt]

I modified the auto fogs slightly yesterday after removing the mod for what I thought was a problem.

I bought a 2 pole single throw switch and wired into the bridging wire, so I can turn the auto fog function off at will. I use it in winter, but not in summer. The switch was $3.80 at a local electronics supplier. At the moment I left the switch inside the panel, but I will mount it somewhere on the dash during the weekend.

 

[Ghost]

Question for a 03 tb owner.
I did this same mod that was posted on t****v**, however if I flash to pass lows come on too if I turn the highs on lows stay on. As of today/tonight I'd like to have my fogs stay on if I use my high beams...the second part for the fogs is this accurate for my particular year make model? Last thing I need is a fire or to mess up my truck
I'm sure this is an old thread (using tapatalk) I just hope someone can chime in before tmrw so I can do the mod and be done playing with the lights n wires.


Note: I do not want the fogs coming on unless I press the fog light switch.

 

[bigytwotone]

i have done this mod and i have the 03 tb and it works but you can not turn off the fogs there on as soon as the headlights turn on.(the not on when the driving lights are on thow) and if you don't have your headlights on and hit the fogs the head lights come on. i hope that helps

 

[Ghost]

i have done this mod and i have the 03 tb and it works but you can not turn off the fogs there on as soon as the headlights turn on.(the not on when the driving lights are on thow) and if you don't have your headlights on and hit the fogs the head lights come on. i hope that helps

Thanks for that info:thumbup:

 

[Matt]

i have done this mod and i have the 03 tb and it works but you can not turn off the fogs there on as soon as the headlights turn on.(the not on when the driving lights are on thow) and if you don't have your headlights on and hit the fogs the head lights come on. i hope that helps

Thanks for that info:thumbup:

That's the only downfall for the mod. But it's a minor inconvenience.

 

[Ghost]

I guess the only way to get my fogs to come on when i want is to rewire the fogs with my own switch

 

[Matt]

I guess the only way to get my fogs to come on when i want is to rewire the fogs with my own switch

Do what I did. Instead of just bridging the wires for the fogs to come on automatically, wire a switch in there instead. That way, you can turn off the auto fogs whenever you want to, which, when turned off, will let you turn the fogs on and off just like the mod wasn't there.

I did it for winter and summer.

 

[Ghost]

Do what I did. Instead of just bridging the wires for the fogs to come on automatically, wire a switch in there instead. That way, you can turn off the auto fogs whenever you want to, which, when turned off, will let you turn the fogs on and off just like the mod wasn't there.

I did it for winter and summer.

Good idea !:thumbup:

 

[Matt]

Good idea !

no worries. You have to work out where you want to mount the switch though. I wanted to mount it next to the other light switches but I ended up mounting it underneath on the knee bolster.

 

[ItsOnVoy]

anyway to do this mod so that the flash and pass is quad also? because my flash and pass is quad now but switching to highs isn't, prefer not to loose one over the other

 

[BO TIE SS]

anyway to do this mod so that the flash and pass is quad also? because my flash and pass is quad now but switching to highs isn't, prefer not to loose one over the other

Look at Post #3 in this thread.

Note: If you've already done the mod of switching the wires, you'll need to put the yellow/black wire back in to #11 before doing this other mod.

 

[ItsOnVoy]

Look at Post #3 in this thread.

Note: If you've already done the mod of switching the wires, you'll need to put the yellow/black wire back in to #11 before doing this other mod.

completely missed that line saying thats what its for thanks! no I have not done this mod yet, should I just follow post 3 then since I have HID's in the lows?

edit: never mind figured it out thanks!

 

[03ltz]

Thanks for the post regulator, The mod was very easy to perform I cant wait to see the difference!!! I'am going to do like matt and put a switch in for auto fogs so that i can reverse it whenever i want. As for the flash to pass I never used it anyway

 

[BOOMERZ]

ok bringing a post back from the dead .... i just installed factory fogs into my LS ( just the fogs in the bumper) and also will have hids installed in the fogs and the low beams , i already have the quad beams mod completed when i first bought the truck ... So my question is can i just tap into the PINK wire behind the headlight switch to have my fogs come on with my low beams ? or do i have to do other wiring ? thanks in advance

 

[NinjuhhNutz]

ok bringing a post back from the dead .... i just installed factory fogs into my LS ( just the fogs in the bumper) and also will have hids installed in the fogs and the low beams , i already have the quad beams mod completed when i first bought the truck ... So my question is can i just tap into the PINK wire behind the headlight switch to have my fogs come on with my low beams ? or do i have to do other wiring ? thanks in advance

if you're talking about using the pink as a relay trigger, then yes...you should be golden

 

[Black-n-Yellow]

Can someone confirm, if using this setup, do the parking lights still come on with the fogs as drls?? also, can you use the switch to kill the fogs and have no lights?
(keep in mind i'm asking about the fogs as drl's setup, I don't want to put in my own switch for the fogs as some have mentioned)

 

[02TrailBlazer]

I just completed the quad beam modification and I did things a little differently mostly because it saved me a ton of time and AFAIK there is not a single downside. (Minus the headlights not shutting off with the delay, which happens with all versions of the mod)

1.Flash to pass functions as normal. (Headlights don't need to be on)
2. You don't have to take apart the factory connectors or cut any wiring.

What worries me though is that there is probably a reason no one has simply spliced the High beam and Flash to pass wires together before, keeping the functionality of both while maintaining Quad beam highs. So if anyone can foresee a downside to my configuration, please let me know because I'm not seeing it if there is one. And if you are comfortable using T-Taps then this just became a 5-min mod.

 

[Envoy_04]

I don't see a downside, however I do know of a way that, IMHO, is easier and keeps OEM functions better.

GMTNation - Alternative method to add a 4 or 6 beam headlight setup

This way retains ALL OEM functions, with the exception of having SIX lights burning on high beam. Did this on my Envoy and it's GREAT, especially for being able to see deer in the roadway (big problem where I'm from). Works great for me as well, as I was a little afraid of messing with the factory harness. This method simply installs a couple diodes in the fuse box up front, and as an added bonus it's easier to get to!

As a side note, the linked post says it's for V8 EXT/XLs, but not to worry - the method is the same for ALL TB/Envoys, 4.2, 5.3, and 6.0, SWB and LWB.

BTW, I've read a lot of posts on here, and I believe you won't see many guys doing it your way because the general consensus here is T-taps are a no-no. I'm not disagreeing with your method working at all, I'm just saying that the T-taps are a downfall.

 

[02TrailBlazer]

Yeah, I totally agree with the consensus on T-Taps; I only used it for testing purposes, I then soldered them together. So far so good! But I am definitely going to toss a switch in the auto fog wire and tuck that behind the access hatch on the side of the console.