So I'm working on this printer for fun and experience for my personal use and have run into a problem I am stumped by. It prints blank pages, it feeds the paper and the cartridges move like they are printing, but nothing appears on the paper.

This machine was put together from 2, both OJ 7310's.
Machine A - Was purchased on craigslist stating it wouldn't feed paper. I thought it might be a roller problem and it was actually the gears on the left side. They were doing something weird, I couldn't tell exactly how they're supposed to work and at that point couldn't dismantle the machine that far, so I put it on the backburner. It appeared to be fine aside from that

Machine B - Was a no power situation brought in by a customer who wanted a new printer. AFAIK it was working fine, it just wouldn't power on anymore.

So I took the formatter from machine A and put it in machine B. It powers up and feeds great. There's no ink on the alignment, self-test or when I make copies. I did a # 9 reset and still the same thing. I replaced the cartridges and this didn't help. I reseated all the cables going to the formatter and this didn't help either.

I noticed there was one connector slot on the formatter which I don't have a cable to plug into. I don't remember unplugging it and I searched pretty good to see if it was hanging somewhere and I couldn't find one. This is the only thing that bugs me.

I am also aware of the issues this printer has with the cartridge ribbon cables being peirced by the cartridge holder springs. There are no holes and I've seen that twice before and it always can't detect the cartridges.

SO, anybody have any ideas??