LED Mod Thread

gpking

Member
Dec 27, 2013
534
Berkeley Springs, WV
A bit of help and then a question:

It should be known that a non-polar LED bulb (one that does not need to be flipped 180°) does not function properly in our corner markers (mine caused back-feeding, flashing my 4-ways during the day when I was signaling).
Likewise, with a polar LED (which only works one-way), they do not function 100% correctly either.
What to do?

I came across these neat things called "towed vehicle diodes" used to isolate two different circuits (RV/towed vehicle) and prevent back-feeding.
https://www.amazon.com/gp/product/B0002Q81Y4/?tag=gmtnation-20
61RAufikAeL._SL1500_.jpg


As soon as I saw these things, an LED went off in my head, and I thought installing one of these could get some useful functionality out of my very bright LED corner markers during both the day and night.
Here's what I did:
t10diode.jpg
1) I cut the T10 socket out
2) I soldered one side of the socket to a ground wire (which connects to the 10mm bolt on top of that metal cross member where the front quarter panel also attaches)
3) I attached spade connectors to the remaining wiring, connecting the "OUT" to the remaining side of the socket, and the signal/park lamp wires to the "IN"s

Now my corner marker lamps function as turn signals during the day, and solid running lamps at night (they do not alternate-flash at night).
This will work with either type of LED bulb, and even with normal incandescent bulbs, but it's really only useful for LED's.

Question:
Now, 4 diodes come in a pack, so what to do with the other two?
I had roughed in the control circuitry to use my LED fogs and LED reverse lamps as auxiliary work lights a while back, however, I couldn't find where the reverse lamp wire came out of the fuse block!
I have installed the remaining two diodes behind my tail lamps, but I can't figure out how to route a wire from my relay at the rear fuse block to both of the tail lamps.
What's the easiest way to get a wire from the rear fuse block to the tail lamps without drilling through the floor?

Bonus tip: Likewise, these diodes could be used to add strobing functionality to the existing reverse/tail bulbs for those of you POV people.
 

Blckshdw

Original poster
Moderator
Nov 20, 2011
10,665
Tampa Bay Area, FL
Those would be really useful if you had push connections in place already, for sure. But since you have to cut into your wiring, splice things together and add a ground wire, it would have been a lot cheaper to just buy four 3 amp diodes from any electronic component store.

This is the same basis for anyone who would want to tackle front corner switchbacks as well, just need to add the circuitry in place of this device. :twocents:

As for finding a desirable place to tap the reverse signal, I'd look in the wiring diagrams in the manuals from Mooseman's thread. There should be some options available to you (tail light harnesses, BCM, etc), don't know where they all are off the top of my head.

For getting wires back to the tail lights, pull the side panels in the cargo area. There will be wiring harnesses for the tail lights on either side, going through a rubber boot passing to the area behind the light. You can puncture that to run your wires through, and use some RTV to seal it back up when finished.
 
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gpking

Member
Dec 27, 2013
534
Berkeley Springs, WV
it would have been a lot cheaper to just buy four 3 amp diodes from any electronic component store.
Unfortunately, I don't have any hobby electronics stores within at least an hour drive. It's horrible.
By the time you factor in shipping on regular diodes, these ones aren't a whole lot more expensive, plus I liked the look of these. The connectors are even included.

For getting wires back to the tail lights, pull the side panels in the cargo area. There will be wiring harnesses for the tail lights on either side, going through a rubber boot passing to the area behind the light. You can puncture that to run your wires through, and use some RTV to seal it back up when finished.
I did finally manage to figure this out on my own once I popped the driver's side boot out and realized I could see inside the vehicle. Duh! For some reason the wiring diagram made me think the wiring ran under the body somewhere and I just couldn't find it.

All is working! Pressing the fog light button cycles through lighting options, and it puts out some serious light. I shouldn't hardly need my flashlight anymore.
 
Mar 30, 2016
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Unfortunately, I don't have any hobby electronics stores within at least an hour drive. It's horrible.
By the time you factor in shipping on regular diodes, these ones aren't a whole lot more expensive, plus I liked the look of these. The connectors are even included.


I did finally manage to figure this out on my own once I popped the driver's side boot out and realized I could see inside the vehicle. Duh! For some reason the wiring diagram made me think the wiring ran under the body somewhere and I just couldn't find it.

All is working! Pressing the fog light button cycles through lighting options, and it puts out some serious light. I shouldn't hardly need my flashlight anymore.

Damn.... That Looks Sweet!!!

Waiting for a write up soon !!!!
 

gpking

Member
Dec 27, 2013
534
Berkeley Springs, WV
Damn.... That Looks Sweet!!!
Waiting for a write up soon !!!!
This is specifically tailored for my setup, so a write-up would be pointless, but I will give you a rundown of the main parts I used in case you want to try and recreate something similar:

-OE Fog Light Button
-PAC TR-7 (brains of the operation, acts as a latching relay, provides the cycling functionality, mine is in mode #16)
-A few SPDT relays (the fog lights also work as DRL's so I have some basic relay logic going on under the dash)
-Add-a-fuses
-2 towed vehicle diodes (to interface with reverse lights)

Basically all you need to make the fog light button do crazy things is the PAC TR-7 and some creativity.
 
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Mar 30, 2016
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Led Mod on the door handle
11mgw03.jpg

Looks good. I was planning on doing something similar but on the outside door handles.

Now I was sitting around with nothing to do to my TB and thought might as well get some good light output. My headlights suck even with HIDs due to:

1. No Projectors
2. They so dirty from the outside even though I waxed them they bad again

I see all those LED strips you can attach to the cars bumpers all over the city. Where would be the best place to attch this on the front bumper and if I was to want then to come on with the engine how would I go with the wiring?

All ideas are welcome
 

Blckshdw

Original poster
Moderator
Nov 20, 2011
10,665
Tampa Bay Area, FL
Where would be the best place to attch this on the front bumper

You're the only person that can answer this question, because the best location will vary from person to person. Pick where you want the strips, and make it happen. :yes:

if I was to want then to come on with the engine how would I go with the wiring?

Post #1 of this thread. :twocents:
 
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Blckshdw

Original poster
Moderator
Nov 20, 2011
10,665
Tampa Bay Area, FL
I've seen LED strips inside of the fog light openings on trucks that didn't have OEM fog lights, but not in the tow hook holes, although I'm sure it looks pretty similar.

Edit: Found this one from one of our former members on the OS

grill3.jpg
 
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Mar 30, 2016
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I've seen LED strips inside of the fog light openings on trucks that didn't have OEM fog lights, but not in the tow hook holes, although I'm sure it looks pretty similar.

Edit: Found this one from one of our former members on the OS

grill3.jpg

Heyyyyy. That Truck looks familiar. I think I saw it in a video on Youtube of a Gibson Exhaust setup.

Sadly the previous owner took it to a "good" shop to install them and its a mess! There's a TB near my house which has the LED strips above the tow hooks, like after the 'cut'. Looks good at night but looks meh in the daytime. Hence I was thinking of 'hiding' them below the tow hooks. We'll see still thinking :biggrin:
 

Blckshdw

Original poster
Moderator
Nov 20, 2011
10,665
Tampa Bay Area, FL
Yes that's the same truck.

Of course what you can, and should do, is take your LED strips and mock them up with some tape and a battery to see how they would look before actually installing them. Make sure it looks as good in real life as the idea does in your head. That will save you a ton of time
 
Mar 30, 2016
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Yes that's the same truck.

Of course what you can, and should do, is take your LED strips and mock them up with some tape and a battery to see how they would look before actually installing them. Make sure it looks as good in real life as the idea does in your head. That will save you a ton of time

I knew it :2thumbsup:. That's actually a great idea. I sure will :thankyou:

On a side note, its impossible to see if you're online or not. Any ideas or is this from my end ? :confused:
 

Matt

Member
Dec 2, 2011
4,019
On a side note, its impossible to see if you're online or not. Any ideas or is this from my end ? :confused:

You can see, if there's a green dot next to the members avatar on their post, they're online, no green dot, they're not.
 
Mar 30, 2016
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You can see, if there's a green dot next to the members avatar on their post, they're online, no green dot, they're not.


Yep. But usually there is no dot beside Blckshdw's avatar and he suddenly replies. But.. lets keep it on topic before he pulls up in his cruiser :popo: :rotfl:
 
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Mar 30, 2016
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I have some intresting projects comming up,will post very soon.
S8ugDE2.jpg


NOOOOOO!!!! You beat me to it with the carbon fiber gear shifter....:Banghead:

That green looks good on the steering wheel. Personally I'm an an blue interior person and Green is a hard color to get right IMO. :2thumbsup:

Now to save yo to buy that steering wheel with the wood from and Black leather I always wanted :quiverlips: :sadcry:

@gpking

Your Profile picture seems to be what I want to do to my TB installing an led strip. Could you post some front pics? Pretty please!!! :book:
 

Mike534x

Member
Apr 9, 2012
894
It took forever to go through this thread, seeing all the pics convinced me to convert my interior lights to LED. Purchased the ones I needed the day before and got them tonight, ran into a small snag while installing them. My EXT came with a rear DVD overhead unit, and the bulb just doesn't fit in the socket. The bulb it came with is a lot thinner/tad bit smaller then the 31mm I bought to put in place of it. Of course, the original bulb has nothing written on it indicating its size. Otherwise, I'm loving how "clean" it looks, only did the rear but gave up doing the others until the rain passes.
 
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Blckshdw

Original poster
Moderator
Nov 20, 2011
10,665
Tampa Bay Area, FL
@Mike534x Have patience grasshoppa, you will find your way...

Feel free to post pics of the oddball bulbs, maybe some of the many eyes here may recognize them. :yes:
 
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FearlessAZ

Member
Jun 7, 2016
156
Phoenix, AZ
I've seen LED strips inside of the fog light openings on trucks that didn't have OEM fog lights, but not in the tow hook holes, although I'm sure it looks pretty similar.

Edit: Found this one from one of our former members on the OS

grill3.jpg

Man, that looks nice. One of these I will dust off the TB and start doing LED conversions. Had the vehicle for about 3 1/2 years and have always wanted to do most of these
 

Mike534x

Member
Apr 9, 2012
894
@Mike534x Have patience grasshoppa, you will find your way...

Feel free to post pics of the oddball bulbs, maybe some of the many eyes here may recognize them. :yes:

Thanks Blckshw, got it situated! The bulb was a DE3175. I guess the LED version is a bit bigger, that and I didn't try putting into the socket, but it went it without an issue. I will say, I'll need to warn anyone who sits back there not to look directly into the light haha. Now that the interior is done, the mod bug is still itching, and I'm strongly considering doing a conversion on the headlights and brake lights.

Headlights are still debatable, I was going to try out the PIAA Xtreme White Plus halogen bulbs to see how they are before going the LED/HID route. Haven't seen anyone on the forum use these, so if I do get them, I might be the guinea pig.
 

GeoGoGo

Member
Dec 29, 2015
166
Upstate NY
Mike,

I had the PIAA Extreme White 9004s in my 95 Caprice. The light output was great and I was very impressed with them. Especially since the Caprice had possibly the worst designed headlamps ever created. They were a little pricey, I think $75 for the pair but for halogen, I feel they were the best money can buy.
 

07TrailyLS

Member
May 7, 2014
423
Toledo ohio
Finally got around to doing a lil documentation of the module polarities yesterday. First up are the instrument clusters, there are a few slight differences between the DIC and non DIC clusters. Of the 4 contact pads per stock bulb, only 2 of them are used. I put the + sign in the corner where the positive pad is, since there isn't one side or the other like all other modules.

Polarity-DICCluster.jpg


Polarity-NonDICCluster.jpg



Driver and passenger door modules. Since I have an LS with the basic options, I don't know if the other trim level modules use the same light source or have additional bulb sockets.

Polarity-LSDDM.jpg


Polarity-LSPDM.jpg



Rear Wiper Switch

Polarity-RearWiperSwitch.jpg



Manual HVAC

Polarity-ManualHVAC.jpg



Headlight switch. I did notice the circuit board is stamped for GMT370s, so there may be differences with the short wheel base versions. I know some have a light under the dimmer knob.

Polarity-HeadlampSwitch.jpg
Sorry for bringing back a page 1 post but I just got my soldering iron and my Leds back out to finish doing the headlight switch, passenger and DDMs, and rear wiper switches. @Blckshdw I am just wondering why you ran the wires on your driver and passenger door modules. Is it the same thing as just soldering the LED in the + and -?? Thanks man
 

Blckshdw

Original poster
Moderator
Nov 20, 2011
10,665
Tampa Bay Area, FL
@Blckshdw I am just wondering why you ran the wires on your driver and passenger door modules. Is it the same thing as just soldering the LED in the + and -?? Thanks man

When you get your PDM/DDM open, it will be a bit more clear. The contact pads are designed for filament bulbs, that emit light in all directions. There's a clear light acrylic diffuser that the 'meat' of the stock bulb passes through, and that's how the buttons get lit up.

With LEDs, since the light is emitted from a much narrower beam from the top only, if you put LEDs in the stock spots, you'll get almost zero usable light. So I ran wires to allow me to put an LED under each button. :thumbsup:

I drilled holes through my diffuser for the LEDs to pass through, and hold them in place, since you can't reposition them and close the modules at the same time. :twocents:
 

07TrailyLS

Member
May 7, 2014
423
Toledo ohio
pretty sure I understand. You just ran leds paralell from your main wires it sounds like. Thanks man.
 

07TrailyLS

Member
May 7, 2014
423
Toledo ohio
ok. I got the lights all wired up and tested them. I wired in parallel to 1 circuit. Well low and behold my negative wire shorted at the source on one of the little solder points on the main board. It must have compressed when I put top and bottom plastics together for bench test. Before I try this again in effort not to fru. my other set of +- traces I'll ask this. I didn't do anything wrong by using 5 LCD's wired to only one set of circuits correct?
 

Blckshdw

Original poster
Moderator
Nov 20, 2011
10,665
Tampa Bay Area, FL
lol, that damned auto correct :raspberry:

5 in parallel isn't an issue, since the current draw of LEDs is so small. Pics of your setup would be more helpful in determining where your issue might be. :yes:
 

07TrailyLS

Member
May 7, 2014
423
Toledo ohio
I know where it shorted. Makes me mad I didn't notice it before everything went together. It lit up for 10 seconds. Flickering like crazy and it was bright as all hell. But the. Poof. As long as I can keep all 5 wired together still then the fix should be as easy as moving the main + and -. As for that damn autocorrect, I find myself editing posts every single time I post. Sad part is I always proof read what I post and I STILL miss things my iPhone corrects :bonk::book:
 

07TrailyLS

Member
May 7, 2014
423
Toledo ohio
Replaced all the LEDs I used on the first go around. Rewired everything and no dice. I just cannot get these things to fire. Checked my solder joints and even though I am terrible at it all the joints are tight and should be accepting voltage. Although embarrassed I'll post a pic to see if you can spot a flaw in the wiring
 

Blckshdw

Original poster
Moderator
Nov 20, 2011
10,665
Tampa Bay Area, FL
Replaced all the LEDs I used on the first go around. Rewired everything and no dice. I just cannot get these things to fire. Checked my solder joints and even though I am terrible at it all the joints are tight and should be accepting voltage. Although embarrassed I'll post a pic to see if you can spot a flaw in the wiring

So just the lights don't work? Or is the functionality with the buttons dead too? Did you verify voltage and ground at the contact pads with a meter to be sure the LEDs aren't the problem? Do your other modules light up when you activate the parking lights? Cover your bases to eliminate potential causes of your issue. :twocents:
 

07TrailyLS

Member
May 7, 2014
423
Toledo ohio
To touch base. Everything works. Windows roll up down etc. I rewired the lights several different times. I don't have a multimeter. I've just come to he conclusion that I messed up the sets of +- traces on the circuit board. I put it back together for now. I'll try the passenger side this weekend and hopefully I have better luck. It just upsets me because I'm not the kind of person who can't get something to work. After a few try's I ALWAYS get whatever I mod or fix to work flawlessly. But thanks so much for the help @Blckshdw.
 

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