LED turn signal issues
 

So I have United Pacific LED lights all around and my turn signals don’t work when my headlights are on but when they are off the turn signals work but as soon as i flip the switch the brake lights get bright as if you’re stepping on the brakes and don’t blink at all. I added 2 grounds in the back off the bed to frame and one off the block and frame.

Thanks ,
Ramiro

Re: LED turn signal issues
 

Do you have the United Pacific led flasher? I had the exact problem you are describing and I believe that was the fix.

Re: LED turn signal issues
 

JMD,

Yes I have the LED Flashers with the ground cable on them.

Thanks,
Ramiro

Re: LED turn signal issues
 

Are they United Pacific brand flashers though? There’s something about their flashers specifically that make them work with their LED tail lights.

Re: LED turn signal issues
 

JMD, not sure which brand my son purchased.

Ramiro

Re: LED turn signal issues
 

I've read installing a reverse polarity flasher is sometimes required. This maybe what you need.

https://www.raneystruckparts.com/led...tension-wires/

Re: LED turn signal issues
 

EL_C10 i have one of those flashers with the ground cable. The one my son ordered didn't come with the lower base.

Ramiro

Re: LED turn signal issues
 

While it will be a bit of time before I can install my United Pacific LED lights, this is what their flasher looks like. When I ordered from Speedway, they recommend this United Pacific flasher.

Re: LED turn signal issues
 

EL_C10 i have one of those flashers with the ground cable. The one my son ordered didn't come with the lower base.

Ramiro

Re: LED turn signal issues
 

Thanks, Rich72C10. looks like we need to purchase a new pair of flashers. Ours doesn't have the reverse polarity base.

Ramiro

Re: LED turn signal issues
 

Rich72C10 so If i purchase those new flashers with the reverse polarity base. Will that take care of my problem with the turn signals not working when the headlight switch is turned on? they work with the headlight switch turned off.

Ramiro

Re: LED turn signal issues
 

Hi Ramiro0727 - I couldn't say either way (I have my doubts). My brother still has my truck, he is finishing up a full SBC/TH350 rebuild. I am just collecting "parts" for little upgrades for it when it gets back into my hands!

But I am converting all the lights to LED. I got them from Speedway and most of them are United Pacific LED.

I just thought I post a photo of the United Pacific Flasher, so you could easily see it. In about two months I'll be able to feedback any issues I have or success :)

Re: LED turn signal issues
 

Ramiro- Im running LEDs all around (Except turn signals, those are next) and I can honestly tell you every truck is slightly different. What works on some doesnt always work for others. I will keep you updated once I install my turn signal LED lights. I might need the fever polarity adapter. I’ll let you know.
Cisco

Re: LED turn signal issues
 

I went through this problem with the lights being fully lit like the brake lights were on when you turned on the headlights. The UP flasher did not fix my issue. I ended up wiring in a dummy 1157 plug into the rear harness to add resistance to the circuit and all works well now. They also sell resistors you can wire in that will do the same thing. Now the UP flasher should help with your turn signal issue though. I had a thread on this in the electrical section about a month ago.

Re: LED turn signal issues
 

Interesting jessemthompson and a good read of your thread (link below). Glad you posted that about your 72 and I'll keep that in mind when I end up doing mine. I suppose this would have the potential to correct two things: Flashing Speed and

Tail light issues

While this YouTube is clearly for a newer Chevy, I suppose this 25 Watt load resistor could be the fix for the Brake Light intensity issue? I suppose this would have the potential to correct two issues: Flashing Speed and Brake Light intensity. Heck I might do this and return the "Flasher" and get a few bucks back.

How to Install a Load Resistor for LED Tail Lights

superbrightleds.com 1969 Chevrolet C10 Pickup Load Resistors
LED Light Load Resistor Kit - LED Turn Signal Hyper Flash & Warning Fix - 50W LED Load Resistor kit

Current Draw 2.25A (2250mA)
Ohms 6 Ohm
Wattage 50 Watts

O'Riley's
Sylvania Load Resistors For LED Mini Bulbs (Pack of 2)
Part # LOADRSLBX2

Re: LED turn signal issues
 

Due to heat that would occur with load resistors, I am thinking about these. If I am needing them after updating to LEDs (if I have Brake Light intensity issues).

Morimoto HD Load Resistor

Re: LED turn signal issues
 

Those LED Flashers, like above, contain a load resistor.

Re: LED turn signal issues
 

Interesting, which would make sense. I am not doing bulb replacements but whole light/lense replacements from speedway. I am just reading every thread I can on this subject to be ready for anything that pops up! I'd be very happy they they all just work but I do plan to install one at a time and test as I go too!

Re: LED turn signal issues
 

I ordered a pair of the reverse polarity adapters. Also I’m going to take a look at my turn signal switch.

Ramiro

Re: LED turn signal issues
 

You need the reverse polarity switch for the turn signal side, but not the hazard side.

Re: LED turn signal issues
 

I did the same thing with my truck.Had to put a couple of old style bulbs back in to make everything work right.Something about not enough voltage being drawn.

Re: LED turn signal issues
 

Bobbysgmc. Where did u put old style bulbs at? All the lights in my sons truck are LEd.

Ramiro

Re: LED turn signal issues
 

You have to wire in an additional 1157 plug. I did it under the bed of the truck. Just cover the bulb and wire it in before it splits between the tail lights.

Re: LED turn signal issues
 

Jessemthompson wire it before the the 2 lights? To which colored wire?

Ramiro

Re: LED turn signal issues
 

here is a wiring diagram - I assume the colors are correct - I got it from another thread that I have saved on this subject. Posted by Andy4639

Information needed on LED side marker lights

boo - its a thumbnail and you cannot see the original size but you can get the full size from the thread above.

Re: LED turn signal issues
 

My 71 has all LED in it. No problems at all with anything. Everything works like it's suppose to. Both flashers are LED with grounds. No need for the old bulbs to be put in at all. Just fix the wiring so it's right.:chevy:

https://www.youtube.com/watch?v=KEwca2XGBVM&t=6s


https://www.youtube.com/watch?v=TxGB0TewBqU


https://www.youtube.com/watch?v=XIOwg83B9Fg

Re: LED turn signal issues
 

Andy4639 the problem I’m having is when I turn on my headlights the rear turn signals don’t work and the tail lights get bright. I added 2 new grounds from the frame to the bed. All my wiring is new.

Ramiro

Re: LED turn signal issues
 

Then I would think your new wiring is not correct. You wouldn't be the first to have a wire crossed. The LED lights do not like crossed up wires.:chevy:

Re: LED turn signal issues
 

My wiring was absolutely fine and I had to add a dummy plug to get the brake lights to operate correctly. I had the same exact problem. The dummy plug fixed it. It’s that or putting resistors in. I’m pretty sure it was the brown and yellow wire. I tapped in to the intermediate rear harness. Right before the plug. Make sure you put a good bulb in it and then be sure to cover the bulb.

Re: LED turn signal issues
 

jessethompson I received the polarity reverse adapter today. I've added it and it did not make a difference. I guess its time to add dummy plug. Could the dummy plug be a plug for the side markers?

Thanks,
Ramiro

Re: LED turn signal issues
 

Here is what I think you have going on. Tail and brake lights are supposed to work like this when you have a conventional bulb. The bulb has 2 filaments. One of the pads on the bottom of the bulb is for power supplied to a very dim filament, that is used for when your headlights are on. It is the running light or parking light. The other pad on the bottom of the bulb is for power supplied to a very bright filament. That is for brake or turn signal. So, if you have brake applied and while your brake is applied you turn on the headlights, you will notice almost no difference in brightness. That is because you are adding something like 2% more brightness to a bulb that is glowing at 98% brightness already because you have the brake applied.

So now imagine what would happen if the filament connections were reversed. You get a very bright running light because your headlights are on, and if you use the turn signal or apply the brake, it only gets 2% brighter. You probably wouldn't even notice the difference. Especially in the day time. I see a huge number of tail lights in cars that people have modified from factory, especially Jeeps for some reason. A large number of LED lights come from the manufacturer's wired backwards if they have a bulb base wired onto them. And if they are hard wired by the person making the "upgrade", that person just doesn't pay attention.

The knobs on either side of the base of the bulb plug are at different distances or heights from the bottom of the base where the contacts are. That is supposed to keep you from getting the bulb in there backwards. But if the bulb is made wrong, or if you force the base into the socket backwards, either of those conditions can cause the problem. Somebody helping my daughter with bulbs did that to her car, forced the bulb in the wrong way. It cracked the socket because the socket was plastic, and I did not appreciate that and had to repair it. But the filaments were reversed and it had the symptom I describe.

I see Jeeps in my area all the time that have LED lenses where the dim outer ring of LEDS is supposed to be for running light, and the bright inner spot of concentrated LEDS is supposed to be for braking, but they have it wired in reverse. The running light is bright as heck when following one of those guys, and if they apply the brake and that dim outer ring of LEDs come on, I can barely tell, unless I'm paying close attention.

Here is how to troubleshoot and resolve. Remove an LED light and take it to a bench with a battery or to the front of the truck. Use alligator clip test wires. Connect the negative battery post to the base of the bulb. Connect the positive battery post to a test clip wire and tap the other end to one of the 2 contacts at the base. Figure out which contact makes the bulb grow very bright, that is your brake and turn signal filament. Tap the positive test wire to the other contact on the base and very it glows but not nearly as bright. That is your running light. Use a marker to mark which is which. Go to the tail light socket on the truck. Use a test light or multimeter to figure out which of the 2 pads at the bottom of the socket gets power when headlights are on, and which get power when brakes are applied. Mark which is which. Then verify the correct contact on the bulb is engaging the correct contact in the socket when you insert the base and lock it into place.

It is also a good idea to make sure the truck works with conventional bulbs before trying LED bulbs. You may have done that already.

I think a lot of LED bulbs are made incorrectly and both of the "filaments" glow at the same brightness. In my opinion, those are cruddy. The ones that have different brightness filaments but are wired to the base pads backwards are extra cruddy.

Anyway, sorry that was such as long story. If it leads to resolving the problem, great. If it does not, then I'm sorry, but perhaps the troubleshooting ideas and thoughts will help somebody.

Re: LED turn signal issues
 

Thanks dmjlambert, I will try that also.

Ramiro

Re: LED turn signal issues
 

jessemthompson, Cover the bulb with tape?

Thanks,

Ramiro

Re: LED turn signal issues
 

dmjlambert, I tested the LED light like you advised. I found which connection was the brightest. In the socket of the taillight housing it corresponds to the correct one. I installed regular light bulbs and you could see the light blink. But its very faint. The rear tail lights are just too bright to see it blink when the head light switch its on. I tried a new turn signal switch and headlight switch and I still have the same results. Not sure what to do now. This is ready getting me frustrated.

Ramiro

Re: LED turn signal issues
 

These are $6 bucks from Amazon.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
I have LED's in Otis my avatar and my 40 coupe, the 40 coupe was the learning curve I tried every flasher made for LED's and nothing worked.

I finally broke down and got a hold of one of my sons high school buddy's who became an Electrical Engineer.....he sent me this said throw all those flashers in the sh*tcan and install these.

Everything worked perfectly after I put these in, no regrets....you could have other problems but it sounds like you've covered your bases.

Re: LED turn signal issues
 

Sheepdip, I will order them to give them a try. I have tried everything possible. Everything works fine until I turn on the headlight switch. Also do I connect the wires from relays to the yellow, green and brown wires?

Thanks,
Ramiro

Re: LED turn signal issues
 

Two things I don't understand:
1. load resistors are about getting the flashing module to actually flash. They are not related at all to how bright or dim an LED light glows. So if there is flashing going on but it is just too dim to notice compared to the tail light, why are we talking about load resistors? If I am mistaken please let me know.
2. If the tail light is what is very bright, and the turns signal or brake is only slightly brighter, isn't that exactly what I was talking about being wired opposite and that would indicate wiring or the bulb base or socket is wired backwards? I am talking about post 31 above. You respond "I found which connection was the brightest. In the socket of the taillight housing it corresponds to the correct one." What is "correct one" and let's be clear. The correct connection for the brightest LED is the brake/turn contact, not the tail/running light contact. If your LED has separate contacts and one is less bright than the other, and you ensure the less bright contact is used for tail/running light, then I don't see how you can't resolve the issue.

And one comment: If you have a conventional bulb and it behaves the same way as your LED bulb that indicates the truck wiring is backwards, and the bulb base of the LED is not at fault.

Re: LED turn signal issues
 

I'm no expert nor do I profess to be, I'm simply stating my experience and what resolved the issue. Just trying to give another option to help the gentleman hopefully resolve his issue.

Re: LED turn signal issues
 

The wires coming out of the load cells have no polarity, splice one into the positive or 12 volt side and the other into the ground side preferably close to the LED bulb but not required. Make sure, and I think you have that your grounds and bulb contacts are good.
Put your original flasher (known to be good) back in place. This is how I did it and it solved my non flash issue. I hope it resolves your issue for you.

Re: LED turn signal issues
 

Dmjlambert, when I troubleshooted like u advised me. When I tested the LED light at the battery. One of the connections on the bottom of the LED light socket was britghter than the other one. When I went back to the tail light housing . I verified which one was the contact in the tail light housing when the headlight switch was turned on. It corresponded to the contact on the LED socket that was the brightest when I tested it at the battery. Unless I did something wrong when I tested it. Maybe I should switch the yellow and brown wires around to see if that changes anything.

Ramiro