help with LED tails

[CG-ITS]

Hi guys,

I'm Chris, a student of engineering built in 88.
I was looking for help with my LED tails and came across this forum.

So I recently purchased a set of LED tails for my 04 Tahoe to get rid of the amber section in the rear lights.
I got these: http://cgi.ebay.com/ebaymotors/2000-2006-CHEVY-GMC-TAHOE-YUKON-SUBURBAN-LED-TAIL-LIGHT_W0QQcmdZViewItemQQ_trksidZp3286Q2ec0Q2em14QQhashZitem2554b09b95QQitemZ160334650261QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

But when I installed them everything seemed fine, turn signals, brakes, everything ok, but then cruise did no longer work.
So I took them out again and put the OEM ones back in. Now cruise works again.

It looks like you guys have come across the same problem before, I just couldn't find a solution. How did you master the problem?
Please let me know, I really like this look:

http://www.flickr.com/photos/cg-its/sets/72157622060143897/

Thanks,
Chris

 

[OmarR]

You have to wire in LED load resistors, also called load equalizers.

Search those 2 terms, either here or google, and you will find all the info you want.

 

[dropmech]

You Coast Guard?

 

[Effeckt]

Welcome to the forums first of all. Secondly the first thing I would try is flip flopping the turn signals with the brake since they are both red LED's and see if everything is operational. It sounds silly but since the inputs are the same I could see that being the issue. If the tail lights don't have built in resistors then the only thing you will be able to do is buy them as OmarR said and putting them in.

 

[denalianyone]

I had those led tail lights and three of the led bulbs in the second column were facing in a different direction from the others on the pass. side. You may want to check yours. It was a manufacture defect.

 

[CG-ITS]

Since they were supposed to be plug and play I didn't think I had to wire in load equalizers (is there anything else to them or are they just resistors with heatsinks?). I believe there must be 'load equalizers' inside the light, at least for the turn signals, because they do not flash any faster then they would with the original bulbs.

Switching the connectors won't do me any good I believe because all the LEDs come on for both brake and turn signal.
The connectors are as follows:
One with 3 wires (grnd, tail, brake) and one with two wires (grnd, turn).
Same on the car's wire harness:

Could it be that I need to wire in resistors for the brake lights?

I also checked the LEDs, if they'd be facing the wrong direction they wouldn't light up, right?
All LEDs light up, a bit for tail lights and brighter for turn/stop.

Since in the OEM lights tail/stop and turn are seperate bulbs, I'm thinking that may be where the problem is?

@denalianyone:
What did you have to do to get them to work? I believe you returned them and got a set of new ones, did you just plug them in and they worked or did you do something else to them too?

oO...
Chris

 

[denalianyone]

I returned them and bought an entire new model. I purchased mines from that same seller and the LEDs lit up but when u look at them from a few feet back it looks like three of the bulbs are out. In all actuality they are facing in a different direction from the others.

 

[tast101]

CG-ITS, you look like my buddy named Chad. haha


Danimalmax looks to have your set of light, he wired in some extra light to solve his problem.
http://www.tahoeyukonforum.com/forum/showthread.php?t=178

 

[CG-ITS]

CG-ITS, you look like my buddy named Chad. haha


Danimalmax looks to have your set of light, he wired in some extra light to solve his problem.
http://www.tahoeyukonforum.com/forum/showthread.php?t=178

Haha, tell Chad his forum look-alike said Hi..

Yeah I just came across the same thread and sent him a PM about the aditional lights, asking whether he tried a resistor too, because I'd probably shot the lights out pretty quick here with all the dirt roads I drive....

I have a Fluke 1587 Insulation Multimeter here with me, that can probably do much more than I know about so far, but from what I've heard I believe the Tahoe monitors resistance on the tail/brake lights?

 

[tast101]

I told him earlier, he hasn't responded yet. Prolly sleep or working.

 

[CG-ITS]

crap, need help

Something went wrong here....

So I went ahead, got me 2 resistors (10 Ohms, 10 Watts) and hooked them up with the LED tails. I hooked the resistors up parallel to the brake lights (1 end to the light blue, the other to the black wire).
I did that with the first light and took her for a test run, everything worked, lights, brakes, turn signals, even cruise.
So I went ahead and did the same thing for the 2nd one, everything worked but I couldn't take her on a test run because now she won't start any more...

I put in the keys, everything seems fine but when I try starting her the radio goes off (does it always do that??) and it sounds like the starter is turning a bit, stops, turns a bit, stops, turns a bit, stops... and so on...

I was shocked, checked the fuses, couldn't see anything wrong. Rolled up the drivers side window to go in for lunch and it was going realllllllllly slow...

I've been out there working for like 4 hours now (w/ the radio on), took her on 4 trips of about 300 feet each in between, but I don't think that's enough to drain the stock battery, is it?

OH dang I'm so scared now...
Could I have fried anything by putting resistors in parallel to the led brake lights?

Please say something...............

@tast101: ***, I see what you mean...

 

[T3rry]

your battery is low, just boost it...


you think you only had the radio on, but chances are you also had a door open, that turns on all the courtesy lights, possibly headlights or running lights... if you had the key in then you may have had stuff in the instrument cluster going, HVAC fans, etc... and starting it for 1 minute to drive 300 feet will not charge the battery... give it a boost, go for a good 30 minute to hour long drive and you should be fine.


if it is the stock battery in that truck, i would not be surprised if it's toast, i have found average life for a stock GM battery is about 5 years... i have a 2000 GA, and the battery in that died at about 5-6 years.

 

[CG-ITS]

so I tried boosting it with a Cadillac DeVille with the 4.7 V8 in it, nothing, absolutely nothing happened.

But I missdiagnosed earlier, it's not turning a bit, it's not turning at all. It just goes click click click.... that's it.

So I hooked a multimeter to the battery: 12.2 Volts. Turned on the ignition (noticing all the lights are dimm and everything): 9 Volts.
Tried starting (click click click): 7.8 Volts....
Now I know a stock car battery these days provides 13.8V at idle (nothing hooked up), so that's far from normal.

I just wonder whether it may be something else too? A stuck starter solenoid?
The car has been sitting for a month before and it always started right up.

But I noticed that yesterday and today, after starting it would idle at almost 1300RPM and then slowly go down to regular idle speed.
Now I know that on my dad's 13 year old BMW that's the engine computer that's trying to maintain 14V and slowly but steadily engages the alternator more and more and decreases idle slowly to maintain the 14V, is that the same on the Tahoe?

 

[T3rry]

try taking the battery out of the situation, unhook the battery and put the booster cables only on the battery cables, if it starts, you battery is toast, if it doesn't, it's something else.

 

[CG-ITS]

ok I think my old battery is toast.
Well something good came out of this: Optima Red Top.

It's funny, if I do something and then something else dies I have a tendency to blame it on what I just did...

Oh well, I'm back to the stock lights, but that's because the ones I have here have the same manufacturing defect denalianyone's had. Ugly.
And for all that are reading:

Car is running again, now has a Optima RedTop Battery.
Also, the cruise problem was fixed when I wired 10Ohms, 10 Watts resistors in parallel to the brake lights (light blue to black wires).
But for now the stock lights are back in because the ones I have here have a manufacturing defect (3 lights on the Passenger side are about 45˚ off).

Thank you to everyone for cheering me through this.
I really do appreciate it.
Again, THANKS.
Chris




EDIT:
Now I'll have to find another set of lights...
All suggestions welcome.
All I really wanna do is get rid of the amber.

Any experience with these:
http://cgi.ebay.com/ebaymotors/2002-2003-2004-2005-YUKON-SUBURBAN-TAHOE-LED-TAIL-LIGHT_W0QQcmdZViewItemQQ_trksidZp3286Q2ec0Q2em14QQhashZitem4cead3a54cQQitemZ330357253452QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

 

[Effeckt]

Glad you got it all worked out man. I would have been bugging as well. Those are the same ones that I bought and they do have the built in resistor already. Here's a pic of them on my 01.

 

[AtomicHoe094]

well glad you got it all figured out and it sure as hell looks like you know how to use a ohm reader.. haha

 

[tast101]

Those are the ones we all have pretty much, I like them better than the ones you have now, because all the resistors etc are built in, so they are really plug and play. Just use the thread above I posted because they don't come with instructions and they don't plug in the same order as the stock lights.

 

[Vincent Mitchell]

FYI, I used 6-Ohm 50-Watt resistors and it works fine. You need to do it for both sides. The OP said he wired different ones and the cruise worked. But maybe he didnt have lights on. Cruise will work in the daytime without lights on even without the reistors. But no bueno at night or when lights are turned on during the day, or in low light conditions when auto lights are selected.

When the lights are on, the cruise will not work unless the resistors are wired in. I can confirm it's the light blue and black wires to wire the resistors in parallel to the tail (not brake) light (same housing different wire for the brake light). The car "thinks" a tail light is out when leds are in and the car's lights are on if you don't put the resistors in.

I used electrical plug connectors so that I can remove them easily if/when I sell the truck and put incandescents back in (yes, I am just that cheap). Also, put a long enough pigtail on them so you can mount the resistors to the metal panal adjacent to the lights insid and still be able to open the light lens and not rip out the wiring.

If you have questions fire away. I will be happy to help if I can. Happy wiring!!!

Note, make sure the keys are off and the lights are not on when wiring or you might end up shorting a wire and blowing a fuse. If you blow the lamp fuse for the tail light, it is a 15amp fuse in the fuse block under the hood. Now how do I know that???