Turn signal

Hello, hopping someone can point me in the right direction.
have a 2006 freightliner columbia with a 14l ser. 60 in it.
Had my leftnturn signal go soiled rolling down the road, pulled over to change the bulb. Put 4 way on to find it and they all worked.
withbusing the 4 way and then putting left signal on all but the front worked. Being only 30 mile from the yard I got it home that way.

With everything hooked up four way flashers work and all six position
Right hand turn signal works all down the truck. left hand turn signal only the front left bulb illuminates does not pulsate and the other lights down the truck do nothing

If I unhook the sure power low voltage disconnect behind the display panel
With 4 way neither the front flashers, but mid and rear do on both sides
Right turn signal front does nothing and mid and rear work
Left signal nothing happens to any location
work

With as drl plug dis connected
Works the same as when everyone thing is hooked up ( four way flashers work and all six position
Right hand turn signal works all down the truck. left hand turn signal only the front left bulb illuminates does not pulsate and the other lights down the truck do nothing)

My thought is maybe this low power thing is messing with it, can it cause this issue.
Additionally all the wires in the frount from the firewall to bulbs are good and the rest of the lights work as they should no grounding of any of the plugs or cross over readings.

I greatly appreciate any help.

 

No corrosion
To be seen.
It stays soild and bulb is good swapped with known good same result

 

Replaced it.
I think I found the issue left mid light
Had a wire that I'd I ground starts to work.
But then running lights don't work.
So I know its in that area just need to figure out where the side marker lights run to. In the sleeper

 

Truck is fixed.
Posting so hopefully it helps someone else.
The 3 way break light dispite working and shooting good, was causing the issue. The left front marker light came on and stayed on while other lights did not work.
All flashers worked.
So if anyone has an issue like that change the lights all around to see if issue follows.
Only fond that chasing a short to ground.
I feel pretty stupid for not doing that but now I know.