LED front turn signals question

twinbopilot

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I bought some amber dual-stage 3157 48 bulb LEDs off Feebay and installed in clear corner headlights. Looks killer but stays on "Bright" all the time, even though its a two-stage 3157 bulb. I wired in resistors, spliced between the ground and the "major" wire (turn signal), but still throws a bulb out message when you have the running lights on AND the turn signal. LED turn signal works fine when running lights are off.

Anybody successfully get their LED front signals working right?

I may be able to eliminate the need for resistors by installing an LED electronic flasher unit, but I'm not sure where its located on the car or what the part # is on it. I found a site that said it was a Tridon BSM flasher, but it had no photo and I can't find any further reference to it.

Any and all ideas are welcomed.
 
You want pics??? I give you pics...
4529201754_5d31d3b217_o.jpg

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But no matter how cool they look if I can't get 'em to work right I'm gonna pull 'em out...hopefully I'll figure it out!

They make some other LED 3157 turn signals that stay white as running lights then turn amber for the turn signal. They are a lot more expensive but supposedly have some resistors built in.

Anyone tried them yet? They would look way cool.
 
It would indicate you might need more resistance.
I tried splicing in two resistors to test that theory but got the same result...:(
I put an infrared temp sensor on the resistor and it read 256 degrees f !!! Better be careful where you mount them.
 
Yea i have the chrome ambers in all 4 signals. I like them, especially in the tails.
 
That a crazy looking bulb when it's installed. Looks like an alien turn signal with that warped reflection. Looks cool. How are you putting in the resistors? Me being a genious, I tried using a resistor in the cabin to get the lights to stay off when they aren't in use. I was putting it in series but it had to be in parallel for it to work. Took me like 20 min to figure it out. Just throwing it out there.
 
That a crazy looking bulb when it's installed. Looks like an alien turn signal with that warped reflection. Looks cool. How are you putting in the resistors? Me being a genious, I tried using a resistor in the cabin to get the lights to stay off when they aren't in use. I was putting it in series but it had to be in parallel for it to work. Took me like 20 min to figure it out. Just throwing it out there.

I spliced them across the turn signal wire and the ground, just like the diagram said to do. When that didn't work I tried going across the other line (the running light), but same result. I also found out that the LS does not have a flasher unit, but instead has a BCM or Body control module that runs the blinking of the lights.

Could be a tough nut to crack...:bash:
 
No one has installed LED front turn signals on their LS yet??? How behind-the-times we are! :p
 
I spliced them across the turn signal wire and the ground, just like the diagram said to do. When that didn't work I tried going across the other line (the running light), but same result. I also found out that the LS does not have a flasher unit, but instead has a BCM or Body control module that runs the blinking of the lights.

Could be a tough nut to crack...:bash:

You'll have to put the load resistors between the two wires going to the turn signal. One of the two wires is hot (12V) most of the time, it shuts off about thirty minutes after you leave the car. The other wire is grounded by the FEM anything it wants the bulb to be on. It is this wire that you must supply some current to from the other wire to keep the bulb minder circuit happy, and to stop a slight glow from the LEDs while the bulb is off. The resistor shouldn't get as hot as you indicate. Try something around 2000 ohms. A 1/4W should be big enough. Also note that the LED bulb itself must be connected between the original wires to the bulb socket. If you try to tie to ground or to battery, it won't work correctly.
 
I'm able to make the LED turn signals work, without any message, as long as the running lights are not turned on. The bulb is in its BRIGHT mode as should be for daytime signaling. At this point it all works, even without any resistors installed. So the bulb-minder must not be looking for draw on the turn signal circuit, right?

Now comes dark and the problems begin. When you turn the parking/running lights on, the LED bulb turns on BRIGHT, though it should be on LOW/PARKING only. When you signal, you get the bulb out warning message, and the bulb itself does nothing (stays bright). As soon as you turn off the parking lights, the message goes away.

Now to the way the bulbs work. The original bulb had two circuits, one for BRIGHT and one for LOW. They were independent circuits, with two positives and two negatives (the pins on the bottom of the bulb).

The new LED bulb is a bit different. It has the same four electrical contact pins, but the switching between BRIGHT and LOW is done according to which negative pin is grounded. You can supply power to either positive pin (or both) and the bulb works the same. So in other words, it has two separate ground circuits, and this is how brightness is controlled.

The bulb socket in the car has two negative and two positives as well, BUT it switches power on and off to control the BRIGHT circuit - both ground contacts are on the same circuit. So there is no way to control which ground circuit the bulb uses it gets both all the time.

So if you've followed me this far, is it possible I have the wrong 3157 bulb? Or maybe one that was wired backwards? Or am I completely overthinking this?:confused:
 
I'm able to make the LED turn signals work, without any message, as long as the running lights are not turned on. The bulb is in its BRIGHT mode as should be for daytime signaling. At this point it all works, even without any resistors installed. So the bulb-minder must not be looking for draw on the turn signal circuit, right?

Now comes dark and the problems begin. When you turn the parking/running lights on, the LED bulb turns on BRIGHT, though it should be on LOW/PARKING only. When you signal, you get the bulb out warning message, and the bulb itself does nothing (stays bright). As soon as you turn off the parking lights, the message goes away.

Now to the way the bulbs work. The original bulb had two circuits, one for BRIGHT and one for LOW. They were independent circuits, with two positives and two negatives (the pins on the bottom of the bulb).

The new LED bulb is a bit different. It has the same four electrical contact pins, but the switching between BRIGHT and LOW is done according to which negative pin is grounded. You can supply power to either positive pin (or both) and the bulb works the same. So in other words, it has two separate ground circuits, and this is how brightness is controlled.

The bulb socket in the car has two negative and two positives as well, BUT it switches power on and off to control the BRIGHT circuit - both ground contacts are on the same circuit. So there is no way to control which ground circuit the bulb uses it gets both all the time.

So if you've followed me this far, is it possible I have the wrong 3157 bulb? Or maybe one that was wired backwards? Or am I completely overthinking this?:confused:

Okay, then the gen I must control the lights differently than the gen II. It sounds like you have the correct LED light for the gen II. The gen II has one positive power feed for both filaments of the stock bulb. As I said before, this feed is on all the time, except for after the car goes to sleep. Each of the bulb negatives are switched to ground to activate either the signal light or the parking light.
Your description indicates that the gen I does not operate that way. I don't have gen I wiring diagrams, so I can help much there. No doubt there is a way to make that LED lamp work, but I don't have gen I wiring diagrams, nor a diagram of the internals on the LED lamp, so I'm not sure how.
 
Here's the gen II diagram of the lighting control for the turn signals for the curious.

IMG_0001s.jpg
 
Thanks Joegr but I'm still scratchin' my head over this issue.

I'm thinking about a relay to control the bulb brightness but not quite sure.

A deal just came up on a set of 2005 Gen II Headlights. I may just go that route!
 
The Gen I LS Park/Turn lamps are wired the same as the Gen II. One power wire(12 Volts at all times while the FEM/REM Modules are active that goes to both filaments, Park & Turn), and a separate ground wire to each filament that is controlled by the FEM.
 
Thanks Joegr but I'm still scratchin' my head over this issue...

I'm thinking about a relay to control the bulb brightness but not quite sure...

I think that you would probably need two diodes and one (additional) resistor to make this work. You would use only the bright circuit on the LED lamp. Connect the negatives to ground. Connect the turn signal positive through the first diode to the bright positive of the lamp. Now connect the parking light positive through the second diode in series with the additional resistor also to the bright terminal of the lamp. The additional resistor will reduce the current to the lamp to make it dim for the parking light. I don't know what value the resistor needs to be, but I would start at 100 ohms, probably 1/2W. The diodes prevent the turn signal power from backfeeding into the parking light power, and vice-versa.
Disclaimer: This is all dependent on you having correctly described the gen I operation and the way the LED lamp works, and on me correctly understanding what you have described.
 
The Gen I LS Park/Turn lamps are wired the same as the Gen II. One power wire(12 Volts at all times while the FEM/REM Modules are active that goes to both filaments, Park & Turn), and a separate ground wire to each filament that is controlled by the FEM.

I would have thought that Gen I would be the same as gen II for this, but this is not what he is describing. Do you have wiring diagrams?
 
Joegr, your suggestion makes as much sense as any I've read. I may try that yet.
 
Ok well I SORT OF have them working. Maybe someone smarter than me can explain why it worked, but I folded the positive wire lead on the bulb that goes to the LOW/Parking light circuit OUT OF THE WAY where it could not make contact in the bulb socket. Now I have bright LED turn signals day and night, WITH NO BULB OUT MESSAGE AND NO RESISTORS INSTALLED!!! The only downside is that I have no parking lamps. I still have the amber running lamps in the bumper, so I'm street legal. Now if I could figure a way to power the LOW side of the bulb, I'd be happier than a pig in slop!
 
I would have thought that Gen I would be the same as gen II for this, but this is not what he is describing. Do you have wiring diagrams?

Yes, I have the shop manuals and wiring diagrams for all years of the LS. If I get a chance I will post the diagram for the Gen I, but I think he will have to add a load resistor on each circuit to acheive proper operation from the FEM.
 

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