Flashers stop afterr couple mins+right trailer brake light comes on w/ left turn sign

Check the fuses.

 

Not sure what else it could be. I would say maybe you have a short in your electric cord from tractor to trailer, but that wouldn't explain four ways shutting themselves off.

 

What model Freightliner do you drive?

 

I haven't had any experience with the Century class. I drive a Cascadia, and I've had light problems similar to what you're experiencing a couple times. Both times it was just a blown fuse, simple fix. Sorry I can't be more help to you.

 

Disconnect the trailer pigtail and see if the tractor functions normally. Then I would assume if you have heavy corrosion the problem lies near the marker if that bulb isn't blown. Start with fixing the known problem of the bad marker light. You might have more than one problem like some wires shorting in the same area.

Another popular area for shorts is the pigtail or junction box. Each wire is screwed down and occasionally them screws have a way of coming loose then the wire shorts with the next screw.

That circuit might be protected with a circuit breaker instead of a fuse. They take longer to blow then they reset themselves after they cool down.