I can't help with a Northern lite but I've reverse engineered an AF990 if you think it would help. Of course it will not match yours but just a general reference.
It's interesting that the manufacturers for most brands don't supply this info even though it would expedite maintenance and trouble shooting issues. I've only had a few campers but the documentation supplied with each has been on par with cheap electronics from China with only slightly better English. I assume that with TCs costing between $20K and $50K the manufacture has to keep their profits at max. Sorry, went on a rant.
I found a couple of issues when reverse engineering the AF such as 10 AWG wire used as a supply for a 30 Amp protected circuit and the return was 12 AWG. It may work fine but I can't stand things done half way right.
Solar wiring was similar with 10 AWG down from the roof but the solar connector on the roof had 14 AWG wire pigtails. Also had an inline fuse block going from the charge controller to the battery that was 12 AWG while the wire was 10 AWG. Probably would have worked OK but I had to change it.
