Ok. It's not the bulbs. Out of the three tail lights the center and right one running lights work. The left running light doesn't work. But the left and right blinker light works. Also the center light running light work but doesn't get brighter when the brakes are applied. All the bulbs have been replaced. So WTF is going on I'm at a loss. Thanks in advance for any help.

 

So you're saying the taillight works but the brake light doesn't? And it's not the bulb? I'd suspect the brake light switch.

 

You may have more than one thing going on there. Is your bike lowered, or have mods of any sort around the rear end? If the rear shocks have been lowered a common problem is the tyre hitting the wiring under the fender, causing damage. So take a close look at them. Also check the condition of the wires between the central light and the left and right units.

Electrical problems like this are often actually machanical. That is to say things like damaged wires, or bad grounds due to damp or corrosion. Your brake light problem may be down to a defective switch (there are two, front and rear).

 

There is a main plug for the rear light assembly right under the seat. You can disconnect that plug and use a test light or multi-meter to check for power when you actuate either brake switch (foot or hand lever). You should see power with the application of either.

At that same plug, you can check for power from the left and right turn signals, as well power for the tail light.

From there, you can determine if the problem(s) is/are upstream, or downstream.