Really weird led tail lite issue....

[TerryH]

Hello guys! I'm hoping that someone more electrical than me...and almost anyone is...can shed some light...pun intended...on a really weird deal with my new led tail lites.

When I got the lights installed this week, the right tail lite did not work. There was power in both sides of the plug for the pigtail going to the light so I assumed it must be a bad tail lite which the fine folks at East Coast agreed must be the issue and are sending another tail lite to me. Problem is, that today I began to secure the rear harness to the chassis and figured out that it would be better if I turned the rear harness around because that harness has a short side and a long side. The short side was on the left but is now on the right. Well....now the right tail lite works but the left doesn't.

There is a central plug in the back of the main rear wriring harness. There is 12v at that plug. There is a split harness that plugs into that plug on the main harness with a leg going to each side and then plugs on the end of those 2 legs that plug into the tail lite pigtails themselves. There is power on both sides of all of these plugs but only one tail lite will work. Whichever one is plugged into the short side of the harness. Suggestions anyone?

TIA,

Terry

[Todd Dolfi]

Check the wire it self it may have come lose/broke at the plug..or maybe the prong on the plug/light just needs opened/closed a little to make contact..good luck hope it's something simple

[TerryH]

The pigtail from the tail lite is soldered to the led circuit board with a plug on the other end that plugs into the harness. There is power on both sides of the plug. I thought it had to be a bad tail lite until swapping the harness around today. There is obviously an issue with the harness I just can't get my head around how there can be 12v on the tail lite pigtail itself and the tail lite still not work.

t

[Spawn]

reverse the wires, they have to be positive to positive and neg to neg. if they are backwards they wont work.

[DOOmsman]

. There is power on both sides of all of these plugs but only one tail lite will work. Whichever one is plugged into the short side of the harness. Suggestions anyone?

I would look at the ground connections, it sounds as if you are back
feeding the one side.

[TerryH]

Originally Posted by Spawn

reverse the wires, they have to be positive to positive and neg to neg. if they are backwards they wont work.

Ding, ding, ding!!! We have a winner. The plug was wired backwards on that leg of the harness. Thanks so much Spawn!!! I had no idea. I figured 12v was 12v. Another live and learn! Thanks again!

t

[pachanga90]

Led lites are very fussy,they need a designated power & ground,whereas standard lites will work either polarity(in most cases).

[Spawn]

I ran LED's in show cars. That's where I learned about it. Glad it was that easy of a fix. I am about to install LED tails on mine to cut the battery draw. LED's run a very long time with little draw on the Batteries. I was looking at LED driving lights also but haven't committed on those yet.

[Nate]

LED stands for Light Emitting Diode, most of you here know a diode is an electric check valve. Power only flows one way through a diode. I know some LEDs work with any polarity, that's because they have four non light emitting diodes in the circuit which direct the power in the correct direction so you don't have to worry about polarity.

[pachanga90]

Always check polarity when you install them,Some are polarity sensitive,some aren't.I install a lot of lighting on work-trucks and come across this alot.10seconds reading can save 10 minutes of frustration.