Taillight Issues Diagnosis

[KellyKid25]

Hello everyone!

This is my first post here but have been a long time fan of the forum and TJ community. It is what convinced me to sell my 2022 JL for a 1999 TJ and I have not regretted it once.

I am having difficulty figuring out what is going on with my driver side tail light. Note that both housing are original from 1999 so age may be the culprit.

I replaced the top and bottom bulbs on both sides and the driver side bottom bulb that has two contacts is much dimmer than the rest. I made sure the bulb was good by putting it in the other side so ruled that out. I cleaned all the grounding points and the top reverse bulb is just as bright as the other side so I think I am good there. I also unplugged the light assembly and sprayed CRC electrical cleaner in the plug and light bulb socket before reinstalling.

I did try putting the incandescent bulb back in and it didnt light up at all where the LED gave a faint glow. So there is resistance somewhere. Does anyone have any ideas or suggestions on what to try next? Any ideas would be appreciated.

I am tempted to just replace these 26 year old housings with the Quadratec plug & play LED housings and call if a day. Lol

 

[macleanflood]

Did you replace your flasher with a Novita LM470?

Honestly sounds like corrosion in the socket on the tail light. Might be able to clean that up with a brass brush.

Otherwise I'd recommend the Black Magic Brakes LED tail lights...


View: https://youtu.be/YlbgMX-PlQM?si=mivx1AsOB1MZDuJ4

-Mac

 

[KellyKid25]

Did you replace your flasher with a Novita LM470?

Honestly sounds like corrosion in the socket on the tail light. Might be able to clean that up with a brass brush.

Otherwise I'd recommend the Black Magic Brakes LED tail lights...


View: %5BURL%5Dhttps://youtu.be/YlbgMX-PlQM?si=mivx1AsOB1MZDuJ4[/URL]

-Mac

I haven't yet. My Wrangler is a 1999 so I think I’d need the Novitia EP26. Fixing the rapid blinkers was my next project after getting the light working correctly. Lol

I also just went out and scrapped the two bulb contact points with a flat head to shiny bare metal and no change in brightness unfortunately.

Are those low profile like Metalcloak’s offering? They look wicked!

 

[hear]

Here, let me LLM that for you.

https://chatgpt.com/share/69f0ca11-813c-83ea-95d4-64714299fb39

 

[KellyKid25]

Here, let me LLM that for you.

https://chatgpt.com/share/69f0ca11-813c-83ea-95d4-64714299fb39

Haha I have been using ChatGPT and Gemini to get me thus far but now just going around in circles with it.

 

[TheBoogieman]

Are those low profile like Metalcloak’s offering? They look wicked!

They are LoPro and much better quality than MC.

 

[Unique Username]

They are LoPro and much better quality than MC.

The Black Magic Tail Lights are a far superior product. Unfortunately they are currently made of on unobtainium. If you made a phone call you might score one in raw aluminum finish assuming some remain.

Haha I have been using ChatGPT and Gemini to get me thus far but now just going around in circles with it.

You folks have really got to let go of this ChatGPT thing. AI is going to ruin thinking for all of you.

 

[KellyKid25]

The Black Magic Tail Lights are a far superior product. Unfortunately they are currently made of on unobtainium. If you made a phone call you might score one in raw aluminum finish assuming some remain.
View attachment 685715



You folks have really got to let go of this ChatGPT thing. AI is going to ruin thinking for all of you.

You are not wrong. Which is why I have come to consult with the TJ experts. Haha

At this point, everyone is throwing new taillights at me so maybe thats going to be the best solution. After 26 years maybe these original housings are tired.

All i can think of now is to get a flathead and push down the bulb contact spring and spray some electrical cleaner in there.

 

[hear]

You folks have really got to let go of this ChatGPT thing. AI is going to ruin thinking for all of you.

If you let it do all the thinking for you, then yes.

 

[GATORB8]

They are LoPro and much better quality than MC.

I have the relatively inexpensive MC plastic version and I think those are an OK value for $100, but definitely not what I'd call a quality piece.

 

[KennethS]

You cleaned the contact posts where the solder bumps on the bottom of the bulb make contact, but what about the notches in the side of the socket where the nubs on brass part of the bulb makes ground contact? My trailer lights had corrosion buildup in that area and some steel wool cleaned it up.

 

[KellyKid25]

You cleaned the contact posts where the solder bumps on the bottom of the bulb make contact, but what about the notches in the side of the socket where the nubs on brass part of the bulb makes ground contact? My trailer lights had corrosion buildup in that area and some steel wool cleaned it up.

So the only thing I haven’t done is push in the plate that the 2 brass nubs are attached and spray cleaner into the socket. I dont see any other holes on the socket to get cleaner into or a way to scrub it with my brass brush.

 

[KennethS]

Is the issue with both filaments or just one? I'd think both would indicate a ground issue as that is common to both filaments, and only one having an issue would be related to the wire on that electrical circuit.

 

[macleanflood]

I'd also get a voltmeter on the connectors and check for 12v.

-Mac

 

[KellyKid25]

Is the issue with both filaments or just one? I'd think both would indicate a ground issue as that is common to both filaments, and only one having an issue would be related to the wire on that electrical circuit.

Just the bottom bulb is having issues. The reverse light is just as bright as the other tail light.

 

[KennethS]

Just the bottom bulb is having issues. The reverse light is just as bright as the other tail light.

OK.
The bottom bulb has 2 filaments.
Each filament is powered by one of the 2 spring loaded contacts at the bottom of the socket.
The housing of the socket is the ground terminal.
The bulb makes contact with the ground terminal through the nubs on each side of the bulb’s metal base.
Both of the bulb filaments ground through this contact

So is the issue with both filaments, or just with one?

 

[CharlesHS]

IF after cleaning the sockets and nub terminals, measuring for 12V and installing new bulbs and the problem remains; it's time to remove the tail light housing to inspect and clean the wiring harness connector terminals behind the housing where each housing connects to the wiring harness.
Once you have cleaned these terminals; test for voltage with a multi meter as Mac posted above.

 

[TJ Jim]

If you have a trailer harness hanging out the back they sometimes use crimp connectors to complete the harness. Follow the trailer pigtail and make sure those connections are clean and not corroded.

If you have a trailer pigtail.

 

[macleanflood]

sometimes use crimp connectors to complete the harness.

And sometimes those are ScotchLocs and they guillotine and sever the wire. Good point!

-Mac

 

[KellyKid25]

And sometimes those are ScotchLocs and they guillotine and sever the wire. Good point!

-Mac

I had the tail lights out and sprayed electrical contact cleaner in the side of the plug connected to the tail lights. But from my understanding my TJ still has factory housings with factory hookups.