OBD2 port stopped working

A fellow board member came by yesterday to help me program a new immo key with his new VAG Tacho and wasn't able to connect to the ECU on my 2003 Golf. The port was working a couple of weeks ago when I connected a generic OBD2 code reader to check a CEL. I tried it again yesterday to check and it too could not connect.

Did some reading and found the K-line issue. Pulled the aftermarket head unit and, bingo, found the K-line (grey and white) was spliced to a line on the HU. Thought that cutting and taping it off would solve the problem, but still can't connect with my code reader.

There were a couple of threads suggesting the cluster needed to be replaced, but how do I check that?

Other than that, I'm out of ideas, anybody have any suggestions?

Here are the OBD pins

#1 - From Fuse 5, powered from the ignition (hot when ignition is ON)
#2 - no use
#3 - no use
#4 - ground
#5 - ground
#6 - from T32a/27, from green plug connector on back of Cluster
#7 - from T32/25, from blue plug connector on back of Cluster
#8 - no use
#9 - no use
#10 - no use
#11 - no use
#12 - no use
#13 - no use
#14 - T32a/28, from green connector on back of Cluster
#15 - no use
#16 - From fuse use 12, hot at all times

I had the same issue last night. Tried to download my stage 1 tune in order to upload the stage 5 by Malone this coming weekend. It seems like I removed a fuse from #12 and didn't replace it. I had to swap #16 into the 12 spot and the Flashzilla fired right up. It very well could be that I moved them around when I was investigating some recent AC issues. All is well but I need to go and buy a fuse for the #12 spot. Not sure what it runs but it will be fixed shortly!

Mike