Reversed taillight problem

[Youey]

I've been having this problem long before I took my truck apart and it's driving me off the deep and I've tried everything. The problem is my passenger side taillight is reversed. It's dim when you step on brakes and when you turn lights on its super bright like your stepping on the brakes. Little history I've changed harness for taillights and got an fuse box and wiring from another truck that wasn't hacked up like mine was. I have 3 ground straps one on frame to cab, frame to bed, frame to cab again on passenger side. Is there any way that the other harness I installed the wiring is different? It's from a 67-72 chevy. And should I ground the battery from engine block which it is now, I have a pig tail coming off neg side to frame ? Just need some suggestions this is making me nuts.

[TobyArnot]

It may sound obvious, have you turned the bulb 180deg. in the socket? Or, Sounds like you could switch the two wires going into the socket.

[Youey]

One thing I forgot to mention there led lights, check out the picture which is gonna be upside down not sure how to change it with iphone, driver side is correct passenger side FAIL-

[Youey]

Oh and I do have the led blinker if that's gonna be the next answer. The blinker on passenger side doesn't work with headlights on but driver side is fine, I tried plugging stock light in does same thing so something is wrong somewhere.

[Youey]

Anyone have a break down of what wire does what going to the back of our trucks ?

[Robznob11]

Well you have a resistor in the dim side circuit and there is not one on the bright side, sounds like the wires are reversed, question dose it blink dim too? If so I'm almost positive you need to make sure the bulb is installed correctly or swap the wires. They have diodes in there that allow them to do that.

[TobyArnot]

Originally Posted by Youey

Anyone have a break down of what wire does what going to the back of our trucks ?

Over on the Electrical board, there is a "sticky" showing full wiring diagrams, in color. Open and print both.

---Colored wiring diagrams are FINISHED---

[Youey]

Blinks dim too. Will not blink when headlight are on just full brightness-

[Hugh in NC]

Bad grounds can make really strange things happen. I suggest grounding ALL of your lights, see what happens then.

[Robznob11]

Yep , and if that doesn't work it may be a short in the column

[Youey]

Originally Posted by Hugh in NC

Bad grounds can make really strange things happen. I suggest grounding ALL of your lights, see what happens then.

All of my lights have grounds now, wiring in column is new I bought a new turn signal switch. This really boggles my mind, especially because all my wiring is unhacked and in good shape- I'm gonna have to try moving wires around see if that does the trick

[Robznob11]

It seems a simple switch of the wires should do the trick. The only reason it sounds like a short is because you said they won't blink vwith headlights on.

[Youey]

Which wires would you switch? You have dark green and Brown going to tail light? Brown being power I assume

[Robznob11]

Actually those are both power. I'm nearly positive that the brown is park lights and the green is brake/ turn. And on the opposite side you should have brown park and yellow brake/ turn. The ground comes from the housing being screwed into the bed . Which is why the previous person Said to add grounds. In other words add a wires from the back of the tail housing to the inner bed structure. And from bed to frame. It's also important to clean to bare metal. No paint or rust. Again why I said to take sand paper and clean your bulb sockets and make sure there is no rust. Dielectric grease is good too. If those are not homemade lights, it does not make a lot of sense because the bulb ends have pins on them to clock the ends correctly so that the correct wires goes to the correct side of the light. Which would point to the harness being messed with( installed wrong) or a short. It's possible some how or another you got the bulb end to go in backwards but it's supposed to be newby proof. Lol good luck.

[Youey]

Originally Posted by Robznob11

Actually those are both power. I'm nearly positive that the brown is park lights and the green is brake/ turn. And on the opposite side you should have brown park and yellow brake/ turn. The ground comes from the housing being screwed into the bed . Which is why the previous person Said to add grounds. In other words add a wires from the back of the tail housing to the inner bed structure. And from bed to frame. It's also important to clean to bare metal. No paint or rust. Again why I said to take sand paper and clean your bulb sockets and make sure there is no rust. Dielectric grease is good too. If those are not homemade lights, it does not make a lot of sense because the bulb ends have pins on them to clock the ends correctly so that the correct wires goes to the correct side of the light. Which would point to the harness being messed with( installed wrong) or a short. It's possible some how or another you got the bulb end to go in backwards but it's supposed to be newby proof. Lol good luck.

Yeah there not home made lights just regular trailer turn, brake, running lights, harness is brand new from bed to taillights. These lights needed ground because they are 3 wires and won't work if you don't ground them, which is why I went bedside to frame. Used a wire brush and cleaned terminals plus added dielectric grease to each fitting hoping that would solve my issue- nope thought wrong. And I ruled out it being the light too because I tried other lights in there does same thing- if you switch the wiring to the light it will not work the light right at the connector. So I'm still not so sure what to change in wiring or where. If I can't figure it out I'm gonna have to find something to see if they can figure it out-

[Robznob11]

Does it work correctly with the regular bulb? If you look at my thread led tail lights sneak peak you will see how I build mine. I use a diode on both sides to keep the voltage from feeding back to the other side . Park... Brake/turn. Not all premades do this. But if the other is working then this one should too. Basically if you look at my diagram you will see that the park side just has a 330 ohm resistor to make it dim then when you hit the brakes it bypasses that resistor and gives it full voltage. The two black diodes are like one way check valves voltage can only pass one direction. The blinker portion is handled at the switch in the column. It ground s out the brakes light to make it blink. If you don't have the black diodes this function will not work correctly which is why some cheap led bulbs like apc don't work on our trucks. If you swap green and brown that will tell you if it's a simple wiring problem. If not it's probably something greater like the actual leds your using or in the column. There is no reason they should not blink with the headlights on. Maybe there is a short in the headlights switch on the parking light side.

[67 chevelle]

switch wires that will fix it

[Youey]

It's same whether it's stock stepside lights or led, driver side with headlights on works fine with turn signal acts like it's suspose to. I'll take a look at your diagram, also bringing up headlight switch I wonder if there's something going on in there, like it's grounding itself out only on pass side, but what throws me off is pass side tail is dim with brakes on no headlights- ugh wiring gremlins will be the death of me !

[Youey]

Does anyone know if the Column to harness the half moon connector could have anything to do with it ?

[Youey]

Thanks robz I ended up figuring it out, headlight switch was either loose or something because I greased all the terminals up there and now it's fine go figure. At least I know where to start if it happens again

[Robznob11]

That's awesome! Glad you got it figured out. Gremlins are the pits....