No sign of working as status lights corresponding to ether ports don't light up or blink .. not even on device on the other end of the cable? And you tried with different devices otherwise known to be flawless?
Or no sign of working as no traffic passes despites status lights indicating link?
When i connect eth1 to eth2 of the same troubled device, leds go up, in winbox i see that status of port is running and i can see traffic.
When i connect troubled router to the similar RB952 the led doestn go up, status of port in winbox doesnt change and nothing happens. The same situation is on the working device. When i connect PC - nothing happens as well.