Turn signal staying lit up when headlights on

[graystonelbz]

Go try what I said and see what happens.

I'm gonna do just that....I finally found someone else who also went LED without changing the whole assemblies. I have LED everywhere except for hi/low and fog lights also. I have also changed the interior to all led and had to put some small resistors in the map and individual rear domes for them to work properly as well...Now that I think of it the cargo light needed a resistor also to get full brightness.

 

[graystonelbz]

Go try what I said and see what happens.

did you use the same size resistor for both the 3157's and 194?

 

[SoCalMike]

did you use the same size resistor for both the 3157's and 194?

Yes sir.

50watt 6ohm resistor.

 

[graystonelbz]

Yes sir.

50watt 6ohm resistor.

did you ever have the backfeeding issue that I mentioned of the lisc plate lights and or roof lights faintly blinking with the turn signal on?

 

[SoCalMike]

did you ever have the backfeeding issue that I mentioned of the lisc plate lights and or roof lights faintly blinking with the turn signal on?

No. I don't think I did.

 

[SoCalMike]

The only feed back I got was with the lights on the dash turn signals we're lightly glowing and my tow mirrors turn signals we're lightly glowing. Also had issues with the 194s not acting right with out the resistor.

 

[graystonelbz]

The only feed back I got was with the lights on the dash turn signals we're lightly glowing and my tow mirrors turn signals we're lightly glowing. Also had issues with the 194s not acting right with out the resistor.

One thing I still don't quite follow is that the 194 sockets only have 2 wires going to them, blink circuit and park circuit, no ground at all. I've put resistors on the 3157s and they are 3 wires, blink park and ground. The resistor leads should attach to the blink and ground and in the case of the 194 there is no ground. So I don't understand how the resistor is working on the 194? With two wires on the 194 you are adding resistance from the blinker over the parking light, which in turn would make that resistor extremely hot I would think?

 

[SoCalMike]

One thing I still don't quite follow is that the 194 sockets only have 2 wires going to them, blink circuit and park circuit, no ground at all. I've put resistors on the 3157s and they are 3 wires, blink park and ground. The resistor leads should attach to the blink and ground and in the case of the 194 there is no ground. So I don't understand how the resistor is working on the 194? With two wires on the 194 you are adding resistance from the blinker over the parking light, which in turn would make that resistor extremely hot I would think?

I didn't understand either but it works. Lol I have been running it for about a year with no problems.

 

[graystonelbz]

I didn't understand either but it works. Lol I have been running it for about a year with no problems.

Lol I'm not trying to mess with you, just trying to understand how stuff works. I would think taping into the blink wire of the 194 with the resistor and then grounding the other resistor lead would be the recommended method. But then again thinking hasn't gotten me too far on this project.

 

[PureHybrid]

I'm assuming your LED tails have built in resistors, I'm just talking about changing to LED bulbs. This is what I don't understand...different guys all seem to say they get different results with the same trucks.

They might, I can try to measure resistance if I get a chance

 

[SoCalMike]

Lol I'm not trying to mess with you, just trying to understand how stuff works. I would think taping into the blink wire of the 194 with the resistor and then grounding the other resistor lead would be the recommended method. But then again thinking hasn't gotten me too far on this project.

You should see my wire in up front. All hacked up trying to figure it out. Had to solder and heat shrink wrap all my cut wires from troubleshooting. The only way I got the 194 led bulbs to work was to wire in a resistor with the two wires of a 194 bulb.....

If you get time, look at the front 194 bulb wiring. You will see it's the same two wires coming from the front 3157 bulbs from what I remember. Two hot wires. I didn't understand how it works. It seems like with the headlights off one of those wires is the ground. Then with the headlights on the previous ground wire was the hot wire and the ground swapped to the other wire.


All I know is that it works and it has been working for over a year like this with no problems.

 

[graystonelbz]

You should see my wire in up front. All hacked up trying to figure it out. Had to solder and heat shrink wrap all my cut wires from troubleshooting. The only way I got the 194 led bulbs to work was to wire in a resistor with the two wires of a 194 bulb.....

If you get time, look at the front 194 bulb wiring. You will see it's the same two wires coming from the front 3157 bulbs from what I remember. Two hot wires. I didn't understand how it works. It seems like with the headlights off one of those wires is the ground. Then with the headlights on the previous ground wire was the hot wire and the ground swapped to the other wire.


All I know is that it works and it has been working for over a year like this with no problems.

I hear ya, whatever works!

 

[graystonelbz]

Found this from a thread elsewhere back in 2016... Kinda describes what we've been talking about

I think what is happening is that the truck is using some of the same lamps for turning as running. If this is true, then applying voltage to the driving lamps is backfeeding into the flashing circuit, including your dash directional monitor lamps.
OEM has a single filament bulb for each of the front side lights. One side wires to the Park circuit, the other lead is going to the blink circuit. When Park lights are on, the side filament returns into the otherwise dead blink path and develops a voltage there that is normally not an issue.
When park AND blink is active, the bulb will light only when the other blinking lights do NOT light. Basically, alternating blink. When park is OFF, the sides blink the same time as the others.
Now, when you sub LED's in the system, what little voltage/current got injected into the blink circuit now causes issues, since the new LED blinkers use so little current, therefore the unwanted blink voltage is high, too high.

 

[graystonelbz]

So for anyone interested I have figured out where my back feed is coming from. It turns out it was not any of the signal bulbs at all. It is the LED's that I used for the brake lights. They are not polarity sensitive and are allowing the voltage to back feed because the brake lights and turn signals use a common ground. I would have never thought the brake lights would have had any effect, but when I swapped incandescent bulbs in all the issues went away.

 

[SoCalMike]

So for anyone interested I have figured out where my back feed is coming from. It turns out it was not any of the signal bulbs at all. It is the LED's that I used for the brake lights. They are not polarity sensitive and are allowing the voltage to back feed because the brake lights and turn signals use a common ground. I would have never thought the brake lights would have had any effect, but when I swapped incandescent bulbs in all the issues went away.

My bulbs are not polarity sensitive but they are dual brightness. Meaning when the headlights are on the brake and turn signals are on but at a low light. When I turn on the signals or step on the brakes the will go to full brightness.

That might be part of your problem not being a dual brightness. I'm glad you figured it out. Are you going to find new led bulbs?

 

[04chase]

i didnt see this but i will chime in also .

i had the same issues you did when doing my 07 lbz. i did add resistors to the rear and have all vled bulbs in the truck with retrofit hid's in the denali projectors.

same with the 194 and 3157 will flash opposite each other. i did also change out my drl to be a 3157 socket and work as a parking light during night to match the rest of the lights in the lower housing. i have had a few of the vled switchback (new triton v3 switchbacks) break a leg from the 3157 wedge base and had to solder in new contacts.

I melted an electronic flasher so i went back to stock and added in resistors on the back. I used luxor1 194 led bulbs in the corner turns and they have internal resistance with no polarity sensitivity . they work fantastic with these bulbs.

 

[graystonelbz]

My bulbs are not polarity sensitive but they are dual brightness. Meaning when the headlights are on the brake and turn signals are on but at a low light. When I turn on the signals or step on the brakes the will go to full brightness.

That might be part of your problem not being a dual brightness. I'm glad you figured it out. Are you going to find new led bulbs?

The Vled brake lights I was using are dual brightness also. They are the 3157 50 led in red. When I figured out that it was the brake lights causing the problem and not the signal leds I contacted Vleds and discussed my issue. At first i was going to add resistors to the brake lights, but they informed me the the more expensive 6 led version are polarity sensitive, draw more current and should not allow the back feeding I am experiencing. I would rather just change the led instead of having more resistors even though it means spending more jing. It never occured to me that the brake lights could be causing the issue. With Led's everywhere except the brake lights everything was working as it should. So I will find out in a couple days if the new leds work the same way.

 

[graystonelbz]

i didnt see this but i will chime in also .

i had the same issues you did when doing my 07 lbz. i did add resistors to the rear and have all vled bulbs in the truck with retrofit hid's in the denali projectors.

same with the 194 and 3157 will flash opposite each other. i did also change out my drl to be a 3157 socket and work as a parking light during night to match the rest of the lights in the lower housing. i have had a few of the vled switchback (new triton v3 switchbacks) break a leg from the 3157 wedge base and had to solder in new contacts.

I melted an electronic flasher so i went back to stock and added in resistors on the back. I used luxor1 194 led bulbs in the corner turns and they have internal resistance with no polarity sensitivity . they work fantastic with these bulbs.

Did you have the issue of any backfeeding? I can't even remeber at this point how the signals are suposed to function....Are they supposed to be opposite each other or in unison? And what do you think caused the flasher to melt?

 

[PureHybrid]

The corner marker and main turn signal are normally opposite of each other

 

[Rancelot211]

So add a resistor to the 194s up front or not? Lol kinda got derailed. I havent had much time to dig into it as ive been rebuilding my cluster.