Load shedding

[DVT873]

Had an 8600 last week, pretty much same as ProStar wiring etc. Voltgauge on dash jumping between 14 and about 15.8. High enough to turn on the light and beep the alarm.Took voltage at the alt. Solid 14.7 volts. Go to batts. Solid 12.3 volts. Hmm. Found the nut on the batt post side of the starter solenoid loose by almost a full turn. That post is used as a junction, has about 4 wires on it. Here's what I don't understand. No codes in DLB or Insite. No MIL light, nothing in dash display. Tightened, nut all good. Wonder if this is another one of NStars "ghost" diag items. There is one in AC and another one I can't think of at the moment.