Tech: Quad beam headlight mod

[JKmotorsports]

Can I do this on my 99??

You should be able to use a relay and wire it in the same way as the pre-03 models.

 

[bahollis]

I tried the "foot of wire grounding the low beam" trick yesterday. No luck.

Not to sound like a total Re-Re, but what's the BCM?

BH

 

[JKmotorsports]

I tried the "foot of wire grounding the low beam" trick yesterday. No luck.

Not to sound like a total Re-Re, but what's the BCM?

BH

Yea, the circuits are different in pre-03 models, so you can't just splice in wire at the lights. The BCM (Body Control Module) is a black box located underneath the steering column. On the 03 -up models there should be six(?) connectors if I remember correctly.

 

[bahollis]

Thanks. I'll give it a look tonight.

BH

 

[river rat]

Just did the headlight mod to my 06 today and tested it tonight. The mod was easy--used a 50V 3A diode from RadioShack and the difference is really amazing. Now if those headlight bulbs were HID...

Thanks JK for all the info!!

 

[bahollis]

River Rat, could you post a pic of what you did? It sounds soooo simple, but I have LOTS of wires under the dash. I just don't wanna screw anything up.

Thanks!

BH

 

[bahollis]

Check out the bottom right of this page-

I have a copy of this catalog and I never even saw this!

http://www.lmctruck.com/icatalog/ce/0050.asp

 

[Slammed]

Hey guys I got my relay but my mechanic says if I do this the voltage feedback will burn out my highbeam switch ??? anybody know if this is a fact ??

 

[river rat]

bahollis--just saw your request. I am pretty tied up until Wed of this week--let me snap a few photos and post them then.

 

[bahollis]

Thanks. I really have no idea what I'm looking for under there. I've got tons of wires, and I just had my alarm put in, so there's lots of wires.

Did I mention the wires?

BH

 

[river rat]

Bahollis--here are the pics you asked for!

Image 55 is a shot taken from the floorboard looking up at the underside under the steering column. You can see the parking brake release to orient yourself. Refer to JK's writeup--the BCM is the black plastic module just over the air outlet and has 5 plugs into it. C2 is the gray plug second from the driver's door, with lots of wires in it!! Find the Black wire w/white stripe and put the banded end of the diode on that wire, and the other end of the diode attaches to the pink w/white stripe. I had to take the C2 plug out of the BCM to attach the diode, just unclip the plastic retaining piece and wiggle it out. Once the diode is attached (see pic 53), plug it all back up and it worked like a charm!

I have a 2006 and I hope the wire color scheme is the same for yours--you can check the grounds as JK suggests if you are not sure.

Good luck!

Uh oh--how do you attach images in this forum?...maybe this will work!

 

[Slammed]

BUMP

Hey guys I got my relay but my mechanic says if I do this the voltage feedback will burn out my highbeam switch ??? anybody know if this is a fact ??

 

[bahollis]

HOLY CRAP that's a lot of wires. I tell you, you guys are brave and/or good to be doing this type of mod.

I'd burn my truck up.


BH

 

[JKmotorsports]

Hey guys I got my relay but my mechanic says if I do this the voltage feedback will burn out my highbeam switch ??? anybody know if this is a fact ??

Voltage feedback burning out the highbeam switch? I guess mechanics can say what they want because they're mechanics. Don't worry, you'll be ok. I've learned through all my years working in the automotive field that most "general mechanics" can swap a water pump and replace a few bolts here and there but know nothing about automotive electrical systems except how to replace a blown fuse and a battery.

 

[Slammed]

Thanks for the reply I am doing it this weekend

Voltage feedback burning out the highbeam switch? I guess mechanics can say what they want because they're mechanics. Don't worry, you'll be ok. I've learned through all my years working in the automotive field that most "general mechanics" can swap a water pump and replace a few bolts here and there but know nothing about automotive electrical systems except how to replace a blown fuse and a battery.

 

[Dahlar]

I have hids in my lows,highs and fogs - this sounds like what I was looking for.

 

[D'Hag]

Well, we all know that our trucks turn off the low beams when we switch to highs. Here is a way to have your lows and highs on at the same time.
03-06 models only need a diode.

Weren't we both just exchanging on the mpg thread? :cool2:

What size diode is needed? Or can you give me a Radio Shack part number?

On my '03, I thought I saw headlamp relays in the box in the engine compartment, driver's side. (I could be mistaken. I'll have to look again.) If so, couldn't the diode be placed between the relays there?

Thanks.

 

[JKmotorsports]

Weren't we both just exchanging on the mpg thread? :cool2:

What size diode is needed? Or can you give me a Radio Shack part number?

On my '03, I thought I saw headlamp relays in the box in the engine compartment, driver's side. (I could be mistaken. I'll have to look again.) If so, couldn't the diode be placed between the relays there?

Thanks.

:yesnod:
Don't have a part number, but you can use any 1-3 amp diode. The easiest way would be to splice into the two wires at the bcm.

 

[road1will]

i just did this today. fantastic mod. now i just need to figure out how to wire my lights up so i can have my fogs on as well

 

[D'Hag]

i just did this today. fantastic mod. now i just need to figure out how to wire my lights up so i can have my fogs on as well

Depending on where you live, you'll be asking for a ticket if you're running all four headlamps plus the fogs. Most states specify no more than 4 forward-facing lamps at a time (not including low-wattage marker lights).

Besides-- the Tahoe fog lights are so pathetic, you won't be able to tell they're on from inside the truck!