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2006 chevy
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36 Posts
Discussion Starter #1
I was wondering if anyone has experimented with the curcuit boards in our taillight assemblies?

I had mine apart to replace a bulb and noticed ALL three sockets contain 3157 DOUBLE filament bulbs even though the top (brake/tail) in the only bulb that ever has both filiments powered.

The center bulb only uses the "bright" filament for turn signals and the bottom only uses the "bright" filament for back-up lights.

I was hoping someone with some electrical know-how might be able figure out how to make the center reflector (turn signal) also illuminate the "dim" filament to illuminate both red reflectors on each side to produce quad tails and leave the factory "bright" filament signal flash behavor of the center reflector.

:thx
 

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2006 chevy trailblazer_ls
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1,140 Posts
i tried this one before but after a few trial and errors i gave up.:(

i hope someone can figure this one out. i like the look of quad tail lights too :yes:
 

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chevy trailblazer_ss_3ss
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i tried this one before but after a few trial and errors i gave up.:(

i hope someone can figure this one out. i like the look of quad tail lights too :yes:
I've done it to mine. Its really pretty easy to do, but you will need to crack open the curcuit board to do it and then just run a couple of jumper wires. I did have to get another set of curcuit boards to rob a couple of parts out of them.

Now that I think about it, it took quite a bit of time to do, but it was worth it.

<"(((><

Scott
 

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2006 chevy trailblazer_ls
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I've done it to mine. Its really pretty easy to do, but you will need to crack open the curcuit board to do it and then just run a couple of jumper wires. I did have to get another set of curcuit boards to rob a couple of parts out of them.

Now that I think about it, it took quite a bit of time to do, but it was worth it.

<"(((><

Scott
Details? Info? Pictures? YOU DID THIS???!!!! :hail::hail::hail:

If you can make a how-to that would be great!

Chris
 

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chevy trailblazer_ss_3ss
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Details? Info? Pictures? YOU DID THIS???!!!! :hail::hail::hail:

If you can make a how-to that would be great!

Chris
I did it a long time ago and I didn't take any pics, but I'll see if I still have the old parts laying around here and if I do, then I'll try to put something together for you. It will take some time for me to do this, but keep after me and I'll get it done. You'll need a spare curcuit board to rob a couple of part out of. I've seen them on ebay for just a few $$$. See if you can get at least one of them for the mod!

<"(((><

Scott
 

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2008 chevy trailblazer_lt
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98 Posts
:woot: Nice mod I'd like to try...
Where is what does circutboard look like. I had my tail off yesterday briefly but all I noticed was a single plug. Im guessing the board is buried under the plastic, and you have to break it :nono: What part should I look for on ebay?
:thx
 

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chevy trailblazer_ss_3ss
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:woot: Nice mod I'd like to try...
Where is what does circutboard look like. I had my tail off yesterday briefly but all I noticed was a single plug. Im guessing the board is buried under the plastic, and you have to break it :nono: What part should I look for on ebay?
:thx
The curcuit board is the part that the three light bulbs are in that screws to the back of the taillight. You will need to split it open to do the mod and then just glue it back together.

I just went to ebay and typed in "trailblazer taillight curcuit board" and they came up.

<"(((><

Scott
 

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2006 chevy
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Discussion Starter #8
:woot:
I thought that might be the case, so I already have one on the way just to peek inside.
:woohoo:
You sure could save me some re-invention if you can remember what to do!

Drop me a reply if you need me to post a picture of a cracked open circuit board when my spare arrives. I really wouldn't want to see you break yours open trying to refresh your memory.

Also very nice to know this mod has some service life supporting it to be safe on the electrical system.

:thx :thx :thx
 

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2002 chevy trailblazer_ltz
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Yea i want to see some pictures of these bad boys in action too.

Here are some pics of a circuit board i took apart (from my 02TB)

The board went bad, had to replace it. Then used a flat head screw driver to pry it open. Real simple.

Here are some pics of my board



 

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chevy trailblazer_ss_3ss
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Yea i want to see some pictures of these bad boys in action too.

Here are some pics of a circuit board i took apart (from my 02TB)

The board went bad, had to replace it. Then used a flat head screw driver to pry it open. Real simple.

Here are some pics of my board




I'll need to do some checking to see which prong is the tail light. There is a little more to it than I remembered yesterday. You will need to use a soldering iron to remove the middle light socket and then you have to cut off some of the curcuit board parts off of a spare set and use them to make the center light socket live. I robbed the parts out of one curcuit board to make up a good set.

I'm not good at explaining what I mean. I'll just need to order a set of curcuit boards and do another set for someone here. I'll take pics and do a write up also.

I'll give it a try and see if I can explain it to where you might understand. In pic #1 you can see the bottom left corner has the prong coming out of it. You will need to modify the middle light socket in pic #2 to look like that one and then run a jumper wire from that part of the curcuit to the new one to tie them together. I can't remember, but it seems as though I had to run another jumper wire on the ground side also.

<"(((><

Scott
 

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2006 chevy
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Discussion Starter #12
Somewhat Detailed HOW-TO

Well took me awhile to get back to this post, but it's sharing time!

First you will need ONE spare Tail light Curcuit board (GM#16532713). I got mine from Ebay for $17, but a salvage yard may be a cheaper option?

HOW TO:

Use this is the opportunity to practice on the spare curcuit board as we also need to repeat some of these steps on the stock curcuit board.

Simply pry open the spare curcuit board using a thin flat screw driver to reveal the guts.



Now that you're familar, open both of your stock curcuit boards.

On the spare board, again practive removing the Brake & Turn sockets (Top/Center) by drilling the melted plastic rivit points and prying the sockets up off the electrical contacts. Some down pressure on the electrical traces was needed to prevent unwanted bending of the traces.



Repeat on the stock boards, but ONLY remove the TAIL (center) socket.

Now we'll need to ADD the missing contacts to one of the TURN sockets to match those of the BRAKE socket removed from the TOP.
We will be able to use the spare BRAKE socket so we only have to make one.

We will make another BRAKE socket by adding the contacts of the spare TAIL to the stock TAIL socket.

Remove the metal contacts from the spare TAIL socket.


Now we get a bit artistic. Take a pair of needle nosed plyers and reverse the bends of the metal contacts from the spare socket.



Next we need to add a jumer for the ground contacts.
Remove one of the contacts from the stock socket and add a "U" shaped stripped wire into the contact holes.



Add a power lead wire (~4 inches) to the other contact and insert the new contacts. Pinch them back into the socket using the needle nose plyers.
Solder the connections.
Insert bulb and visually verify your new contacts make good contact with the bulb.



Now just build the other new socket using the same steps from the spare BRAKE socket. (No fancy bending required) :woot:

Install the new sockets back on the stock curcuit board. The trace contacts will be VERY tight now because of the added wire on the ground contacts. I used the empty spare socket placed upside down on the stock socket and tapped lightly with a hammer until the new socket was firmly replaced over the plastic studs.

Strip the new tail power wire and solder to the stock curcuit board. Note that the board has very little clearance right here so strip plenty to reduce the wire diameter in the tight spot.



Quick Test: Plug the modified board into your truck's harness and witness your creation. IT'S ALIVE (hopefully)

Then just put it all back together.

I used a plastic weld product. After mixing, I placed a generous bead on the studs we drilled out eariler to secure the socket. Then applied a bead of plastic weld along the entire OEM sealed edge and replaced the cover.

Cure time is 90 minutes so no need to rush.

Don't forget to replace the rubber gaskets around the bulbs. Then tighten the modified board back onto the tail lens. This creates uniform pressure on the three sockets while your new weld cures and should make a water tight seal along the edge of your new weld.



Here's the look when complete.



Took me about 4 hrs, but most of that was :undecided :duh: :undecided :weird: :undecided
So, with some of the surprises removed, you can probably accomplish this mod in a hour or so.

:tiphat
 

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Northwest Chapter
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Dude you're my hero, I love the Quad Taillights on the new fullsize trucks. Ill probably be doing this come summer when I can be without my truck for a night while I rip everything apart! Props for the great how-to!:thumbsup::tiphat
 

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2006 chevy
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Discussion Starter #15
I love the Quad Taillights on the new fullsize trucks.
Then you might want to consider using the trailer harness to drive your tail lights.

The 4 pin socket provides Left Bright, Right Bright, Dim and Ground. Using this power to drive your lights you would also have QUAD BRAKES and DUAL TURNS more like the Silverado.

Glad to help! :tiphat
 

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chevy trailblazer_ss_3ss
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Then you might want to consider using the trailer harness to drive your tail lights.

The 4 pin socket provides Left Bright, Right Bright, Dim and Ground. Using this power to drive your lights you would also have QUAD BRAKES and DUAL TURNS more like the Silverado.

Glad to help! :tiphat
I'm sorry that I never got around to doing a write up, but yours is better than I could have done anyway. I tried the trailer light converter, but couldn't ever get it to work right. The trun signals had rapid flash, no matter what I tried!

<"(((><

Scott
 

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2004 chevy trailblazer_lt
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115 Posts
Using Envoy boards

I went to the bone yard and found envoy boards...Didn't even realize they were different...But then i got home and found that they were. Took them apart anyway to figure how to make it work... I think using the envoy boards makes it easier because they run two Dual filament bulbs as well but they have 2 dual filament sockets...Just my :m2:
 

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2006 chevy trailblazer_ls
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301 Posts
hey just wanted to thanks for the write up i did this mod today and it looks awesome jusr a lil more uniqueness from the others on the road lol:woot:
 

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So if I understand correctly, quad lights for parking and braking? Just the middle flashes when turning/signaling? What happens when braking and signaling/turning at the same time?:undecided Great writeup BTW.
 
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