2001 Jetta 2.0 No ECU Communication

Hey guys, got a 2001 2.0 Jetta 114,000 miles, and the check engine light is just on not flashing, I just tryed to check the codes and then scanner I used from work says No communication with ECU, so I went over and used my Mac Tools OBD2 scanner and the same thing happened. So I was told that it could be a fuse blown or something and someone else told me that the aftermarket radio could be the problem, but the radio has been in there since the car was new.

So im trying to see if someone here can lead me in the right direction for checking a ECU fuse problem or is this another issue, cause now I can't register the car without it being smogged and I can't smog it cause the check engine light is on. Any help is appreciated.

-Thanks

Do you have the cars ignition in the accessory position with your scanner hooked up? It won't read your ECU it if it's not in that position. Hope this helps.

Yea, I knew that, thanks though!

I figured it out, all I had to do was actually turn off the radio, apparently if you have a aftermarket radio installed I guess most places wire it the same way, but the way they wire effects communication to the ECU, really odd, but its very common on VW's. I figured out my Catalytic Converter is bad, so I need a new one, which sucks because they are so expensive.