OBD II Not Working all of a sudden?

Hey, So I have a 1995 Subaru Legacy Wagon. Now before I hear ” hey idiot 95 didn’t have OBD II it’s only 96 and up ” This car, I can assure you has OBD II. Now here’s my problem. My friend got a OBD 2 scanner and it worked on his car, a 1998. Even though my car has a OBD II scan port, I wanted to make sure it worked with an OBD II scanner. So I plugged it in and it worked, although I had no check engine light, the scanner just said ” No Codes Found ” So all of a sudden the scanner wouldn’t read his car anymore, and we knew the car’s ECU had went causing this. (there were other things that helped us verify it indeed had a bad ECU, meaning scan tools will not read it, and 2 other scan tools would not read it) So before this, we had thought that the scan tool broke, and that was why it wasn’t reading his car. We plugged it into mine, in which it had worked once, and it didn’t read my car either. So now he has a new car, 2000 he plugs the scanner in and it works, read 4 codes on the car. I figured oh, well lets see if it still reads my car, It doesn’t. It read my other car which is 2002, but not my 95 legacy, in which the same tool had once read without fail. All the scanner will say now is ” No LINK ” What I am wondering is what is causing this? The scanner gets power, but says no link. My car has no check engine lights and runs fine, I know the ecu is ok. I haven’t tried another scanner, because i know the one i am using works on other cars. Any ideas on this strange problem? And again my car is OBD II, look it up, there were a few cars with OBD II made in 94/95, Even ETCG says so in one of his more recent videos on scan tools. Thanks in advance for the help!