Calling all OBDII gurus

I recently updated my VAG-COM to the latest interface and beta 5.009 software. This version has "generic obdII capability" because VW is going that way with their manuals. I was dissappointed when I first tried it on my 96 xj last night because it didn't work. After emailing Uwe Ross of Ross-Tec he said I only need pins 4/5, 7 and 16. My xj has wires in pins 3, 4, 5, 6, 7, 11, 15 and 16. When I clipped all wires other then 4/5, 7 and 16 Vag-COM started working and It turned out the pin 15, the ISO 9141-2 L Line was the problem. I'm able to view/monitor most fields listed, rpm's engine temp, intake air temp, timing advance and more. Does anyone know what's on the "L" line and why all the other wires? I would be interested on what others have found. I tried ordering a Digimoto that uses a Elms interface but after two weeks of waiting and it had not been shipped I cancled my order. I don't have any code but just want to know what my xj's computer is doing.

Thanks
JoBo