Aftermarket third brake light

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corneileous

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2018 Ram 1500 Limited 4X4
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Hemi 5.7
Because in in 02 Ram switched everything to normal. You don't understand here and I'll try to explain better man. Ground is also switched for the lights and the cargo/brake switch supply power. In 2002 (1500) and 2003 (2500/3500) this reversed. So the aftermarket companies wire everything in this way. So now the cargo/brake lights are sharing a common ground, and power source, when in fact they should be separate.:)

The four-pin harness on the truck has two circuits, one for the brake lamps which is on a switched POSITIVE (+), and one for the cargo lamps which is on a switched GROUND (-). The circuit on the replacement lamp in this review is not designed correctly and uses a common ground for both circuits. Put that together and what you get is a brake lamp that works correctly but cargo lamps that stay on all the time, even when the key is turned off. On the factory harness the two pink wires run the cargo lamps and the other two wires run the brake lamps.

Well, I don’t know then, because I was told that the reason why there is a lower brightness glow in the first place was because of how the canbus system works, and that there is a residual amount of current in the circuit. The reason why this is even a problem is because it’s now noticeable when you go to upgrade your third brake light to an all LED one, or even if you just simply keep your OEM third brake light and replace the cargo lights with LED bulbs, is because LED bulbs will respond to that one or two volt residual charge that’s left in the system whereas an incandescent bulb will take a lot more voltage for it to even show any sign of life which therefore is why you don’t see it until you switch to LED’s.

But irregardless of all that stuff that you said, again; when I had the same problem on my 2008 ram, when I hooked up my brand new Anzo third brake light that was all LED, I didn’t know I had a problem until the next day when I drove my pickup to work and parked it. That’s when I noticed that my LEDs for my cargo lights were still on at a lot less-bright of a glow. Out of a panic, without having to worry about whether it was going to turn off eventually and not run my battery down or not, I went ahead and got my Phillips screwdriver out and unscrewed the light and then I unplugged it. I later found out later on that it would eventually turn off and wasn’t going to stay on all the time and run the battery down. And just as I said several times already, the way I fixed mine was I went to the same place that the OP went, bought a resistor and spliced each wire from it to the wires that went to my cargo lights and I had no more problem. The glow was gone after that.

But then again, I just realized that the OP has a second GEN so, I haven’t heard of this problem with those older trucks and I don’t know what he means when he says that his cargo lights are always on. I have no idea what he did or exactly what the problem is, or what exactly he’s talking about.

And as far as on my 18, I guess I’d just have to pull the third brake light out to see how it’s wired. Which actually, if memory serves me correctly, Putco; the company that made mine, made it so conveniently to where if you didn’t have the glow, you were fine but if you did, they sent a resistor in the package so that all you had to do was just plug it in to a little wiring harness and boom, your glow was taken care of. As far as whether or not my 18 would have given me the same problem that my 2008 did, I don’t know, because I automatically assumed that since I had that problem in my old truck that I was probably going to have it in my new truck so I just went ahead and plugged it in anyway and my new third brake light works just as well as the original one did.

I give up. Lol.


Sent from my iPhone using Tapatalk Pro
 

Moparfanatic21

U.S. Marine Vet - 0321, Now a Doctor...of Vehicles
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Well, I don’t know then, because I was told that the reason why there is a lower brightness glow in the first place was because of how the canbus system works, and that there is a residual amount of current in the circuit. The reason why this is even a problem is because it’s now noticeable when you go to upgrade your third brake light to an all LED one, or even if you just simply keep your OEM third brake light and replace the cargo lights with LED bulbs, is because LED bulbs will respond to that one or two volt residual charge that’s left in the system whereas an incandescent bulb will take a lot more voltage for it to even show any sign of life which therefore is why you don’t see it until you switch to LED’s.

But irregardless of all that stuff that you said, again; when I had the same problem on my 2008 ram, when I hooked up my brand new Anzo third brake light that was all LED, I didn’t know I had a problem until the next day when I drove my pickup to work and parked it. That’s when I noticed that my LEDs for my cargo lights were still on at a lot less-bright of a glow. Out of a panic, without having to worry about whether it was going to turn off eventually and not run my battery down or not, I went ahead and got my Phillips screwdriver out and unscrewed the light and then I unplugged it. I later found out later on that it would eventually turn off and wasn’t going to stay on all the time and run the battery down. And just as I said several times already, the way I fixed mine was I went to the same place that the OP went, bought a resistor and spliced each wire from it to the wires that went to my cargo lights and I had no more problem. The glow was gone after that.

But then again, I just realized that the OP has a second GEN so, I haven’t heard of this problem with those older trucks and I don’t know what he means when he says that his cargo lights are always on. I have no idea what he did or exactly what the problem is, or what exactly he’s talking about.

And as far as on my 18, I guess I’d just have to pull the third brake light out to see how it’s wired. Which actually, if memory serves me correctly, Putco; the company that made mine, made it so conveniently to where if you didn’t have the glow, you were fine but if you did, they sent a resistor in the package so that all you had to do was just plug it in to a little wiring harness and boom, your glow was taken care of. As far as whether or not my 18 would have given me the same problem that my 2008 did, I don’t know, because I automatically assumed that since I had that problem in my old truck that I was probably going to have it in my new truck so I just went ahead and plugged it in anyway and my new third brake light works just as well as the original one did.

I give up. Lol.


Sent from my iPhone using Tapatalk Pro
Yeah you are taking about 2 completely different systems. The OPs problem is they are on (not dimly lit) because they are wired for the correct way to wire things. I went through the same thing on my 2nd gen. They have PCD Bus where some 01 or 02s came with CAN BUS. It gets a little complicated :)
 
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Royal50

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Wa
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2000
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5.9
I really appreciate all of you giving me your input, really. I haven't been able to get to this this week but I will. Im just going to trace all the wires and one by one try this resistor. I will keep everyone posted. Thanks again.
 

SteadyEddie

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Royal50, we haven't heard from you since July 02. Did you resolve the problem? I have a 1997 Ram and will be changing my 3rd brake/cargo lights soon and would like to know if any responses fixed your problem. I suspect that some people didnt have any issues because the kit they purchased had the resistor built in. I would really like to know what kit they used but I guess thats not allowed on this forum?
 
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