Gen_Crunchytoes

Ok.

-confirmed continuity between circuit ground and body ground
-confirmed continuity between faulty wire and circuit/body ground
-with pedal depressed read 0v coming from faulty wire.
-measured 0v between circuit ground and body ground
-measured .25ohms between circuit ground and body ground

Again, running out of ideas as to what it could be

ej1995

The one wire that is "dead" at the back, can you check it up front and get voltage?

Fabrik8

So the only thing that you know now (that you didn't know before) is that the ground is good. Otherwise, you've just proven that the faulty wire is faulty. You need to trace the faulty wire forward, and see where the voltage stops. Of, you can start from the front and move toward the rear, which is generally the easier way to go. This way you verify the function of switches, connectors, etc., before you start digging around in the harnesses between the dash and the rear taillights.

You already know that the switch is good, because the other taillight works. The switch has a 2 pin connector, so somewhere there is a junction that breaks the single wire from the brake switch into 3 different wires for the left, right, and CHMSL (third brake light). You know the other two lights that connect there are functional, and one isn't. Find that junction and start from there.

Gen_Crunchytoes

Update:

So earlier in the week i replaced the brake light switch, just because i had a brand new one. No change. Took the time today to strip more of the wire loom away and found the junction that brakes the single power feed into 2 feeds (i think theres another junction in the trunk that runs the third brake light). I traced the bad wire from the plug into the junction and saw no broken insulation, burn marks, or anything else to indicate exposed copper or a short. I figured there was maybe an issue within the insulation that hadnt made its way through, so i replaced that entire section of wire and still dont have a functioning brake light.

Out of ideas completely. Might light the car on fire

NasTHatch

Made sure the blinker fluid wasn't low ?

Fabrik8

Now that you know where that junction is, test back from the tail light to that junction, and test the ground as well if you haven't already. This is going to be a simple problem and you're going to kick yourself when you find it.

I told you the brake light switch wasn't the problem, because the other tail light works perfectly fine.

Gen_Crunchytoes

i did test the ground. pulled .001v ground to body so its not an open ground. if i have some daylight tomorrow ill mess with it more. the only thing left really is the pins in the plug, but when i opened the plug up they werent super corroded and no pin was any more loose than the other. i may just end up re-pinning that plug as well if i dont find any other potential problem

i figured since i already had one, might as well do it lol. best case, it somehow fixed the issue. worst case i have a new switch

Fabrik8

All your problems can be solved with a multimeter.

Keep pushing, the problem is right there but you haven't seen it yet...

Gen_Crunchytoes

I've been using a multimeter! At this point the only thing that makes sense is the plug needing to be repinned

Fabrik8

If you test from the connector pin on the bulb side to that wire splice, it sounds like you'll find a break somewhere around there.