Ground Issue - Tail Lights Blinker

[TA_C10]

I have an issue right now where I turn on right turn signal, and right tail light blinker works fine, but the left tail light blinker and left bedside marker light also blinks with it(dull but it blinks). Pretty sure it's a ground issue.

When I hit the left turn signal, it works fine, and right blinker and beside marker don't blink with it.

Only when I hit the right turn signal is my issue. All lights are LED. I do not have my front park/turn/bedside marker lights hooked up yet, this is a new installation.

I checked all the grounds at rear of vehicle, they are all grounded well. If I have a problem in the cab harness, which ground in the wire harness would it be? I don't see a ground connection specified in my new American Autowire harness specifically for the turn signal switch. Does it even have a ground connection for the switch at the column?

I have a new LED blinker relay installed in the fuse panel that has it's own separate ground wire that is connected to a ground buss on my firewall. I checked this and it's good.

Thoughts?

[franken]

The ground paths have to make it all the way back to the battery/alternator so there were a bunch of ground straps.
https://www.google.com/search?q=67-7...hrome&ie=UTF-8

[VetteVet]

IF it is a ground issue the right tail light should also be dim. If they are both bright then you may have a polarity issue with the right LED. I would run a wire from the battery negative to the Led socket as a temporary ground check.

The right blinker may be working fine when you select it because it is finding ground through the left blinker and marker light. Weird things happen when there are poor grounds.

[TA_C10]

That is what is stumping me Vette. Right tail light is bright, left one is dim. And also left marker comes on also dim. All the other features like brake lights and parking work perfect. Only when I hit the right turn signal does the left one join in on the fun dim-ly....

I thought I was going crazy. This ended up being a frame off, so I relocated battery to frame. I ended up building my own PDU up on the core support and I ran everything back through 1/0 awg wire straight to battery. Everything is painted included frame so for the tail lights I went ahead and ran a ground from frame to rear cross member. I thought maybe from rear cross member to bedsides the paint was causing an issue but I took a wire from my frame ground and manually ran it up to the bedsides. No change.

Tell you what though, I painted the tail light buckets too and just relied on the screws to eat through the paint on both the bucket/socket and the bedside clips they screw into. I will just have to take the lights back off again and test them like you said. I will report back tomorrow.

And franken, I went through that thread thanks for the response.

[TA_C10]

Well I found crossed wires up front, had not installed the parking/turn lamps yet. That's the long story short......

But here is a video of my tail-lights in action after the fix. Phone video not great...

https://youtu.be/V9Hj_nIX7WM

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