+Karma to westfw
Still, if you're using the power from the RX.TX line to light the LED, you're taking power away from the signal. Right? It may not be noticeable on short connections but if you're going for long runs (more like RS485), it seems you should use a separate power source and drivers for the LED(s) and not the power meant for the signal.
I came across this topic doing a search on the www for the answer on how to use the LEDs on the RJ45 connectors. I notice drivers on RX/TX lines for LEDs but traces are on another layer of the pcb so not sure where they go. Drivers are new to me..
So this is what I will do, use separate +5, use driver, resistor, send cathode of LED to signal.
Thanks!