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Switchback LED bulb front turn signal issue

Old 10-28-2017, 12:57 PM
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Switchback LED bulb front turn signal issue

I have been trying to change out my front turn signals with switchback LED bulbs. I can get it to work sometimes but the bulb has to sit at a particular position. Other times its stuck yellow or stuck white or nothing at all. I have changed the relay to an LED relay. I am at a loss.


Has anyone else done this? Have you made it work and how? I am not looking to do any custom build like I have seen on other threads.
Old 10-28-2017, 07:35 PM
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Re: Switchback LED bulb front turn signal issue

I have some problems with LED bulbs in my front signal housings. The LED base is not made exactly the same as the incandescent bulb, it is rotated slightly, so the terminals don't sit on the bottom of the bulb like it should. I haven't figured out how to fix it other than you have to modify the housing somehow, or move the little nubs on the LED base somehow
Old 10-29-2017, 10:15 PM
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Re: Switchback LED bulb front turn signal issue

The LED's base really is exactly the same as the incandescent bulb's base, so they should be plug-n-play, and they are... almost.

The difference is the size and shape of the glass bulb vs. the LED, where each connects to its base. And that tiny difference is probably what's causing the problem you're having. I ran into this problem when I installed 1156 LEDs into my reverse sockets a few years ago. And once I figured out the issue, the solution was simple and quick.

You see, the top of the base actually sits deeper into the socket than the top of the socket. And a bulb fits because its glass is tapered smoothly into its base, allowing the base to fit all the way down into the socket, where it can be twisted securely into place. But the LED does not taper into its base; it's mounted on top of its base, and it's fatter than the base(so slightly that you'd swear that cannot be causing the problem, but it is), and that tiny difference is what's preventing a proper fit, by not allowing the base to fit into the socket as deeply as necessary to twist it securely into place. You'd swear it's in there, but it's not... almost is, but not... quite... no matter how hard you push.

Look at the pics below. The bulbs/LED pic is mine that I snapped a few years ago when I did this, and it shows the differences between the standard bulb(center), the LED(right), and another supposedly standard bulb(left--with the same problem as the LED). The socket pic is one I just saved to show you the area that needs to be modified, which will take merely minutes.

So get out your dremel and chamfer/bevel the inner edge of the socket. This will allow the socket to properly accommodate the fatter LED, and its base can then slip that last mm farther down into the socket, where it can be twisted securely into place.



Old 10-30-2017, 09:18 PM
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Re: Switchback LED bulb front turn signal issue

Originally Posted by LAFireboyd
The difference is the size and shape of the glass bulb vs. the LED, where each connects to its base. And that tiny difference is probably what's causing the problem you're having. I ran into this problem when I installed 1156 LEDs into my reverse sockets a few years ago. And once I figured out the issue, the solution was simple and quick.
That is definitely not the issue I have with mine in the Firebird, mine go into the sicket just fine becaues they relieved under the "bulb" just like an incandescent. But I did have your issue with another vehicle. Must be the brand of bulb because the ones I have the pins are not orientated the same as the incandescent bulbs
Old 11-16-2017, 10:46 AM
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Re: Switchback LED bulb front turn signal issue

Originally Posted by scooter
That is definitely not the issue I have with mine in the Firebird, mine go into the sicket just fine becaues they relieved under the "bulb" just like an incandescent. But I did have your issue with another vehicle. Must be the brand of bulb because the ones I have the pins are not orientated the same as the incandescent bulbs

I had the same problem with a set of Pilot brand LED. it only flashed if the lights were off. I bought a set Luyed brand amber lights that were specific for turn signals. These have been working but I did have to modify the pins as I had that bottom out issue in the socket. I got them off Amazon.


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