'01 SAN Upgraded to 100amp Alternator, but still got under 12v at dash gauges

[patoloco]

Not to thread hijack, but having the same problem on a 99 Air. I have no fuse box. All of the ground wires appear to be daisy chained in a big huge mess behind the dash pod.

Where would I run a new ground wire to in that situation? The keyed switch?

[jhiestand]

I hate beating a dead horse, but I've had this issue since my 01 SAN was new and only recently have decided to tackle it. Per the bulk of the threads on this issue I ran 6 gauge wire from the starting battery to the black circuit box +/- leads, but no dice. Although I get a 13v at the battery and at the box, my PP reads over a volt lower and my irritating dash analog gauge even lower than that. Should I be looking for another ground somewhere or am I missing something else?

Especially irritating as I recently put in a digital voltage gauge to monitor my house battery/circuit and it works great. Engine running it displays a healthy 14+ volts and with it off it shows 13+ volts.

What am I missing?

[TX-Foilhead]

Start checking and cleaning contacts inside the black box and between there and the gauges. Every electrical connection is a spot to loose a little bit of voltage so its most likely going to be a collection if weak connections and not just one spot that fixes it. I'm not familiar with the late 90's and up electrical systems, but if you just need for the PP to see more voltage then getting a hot closer to the black box instead of off the tach may help. I know on my 93 even with the electrical upgrades the PP draws it down about 1 volt after the servo does its check before the boat is started. That's enough to make the PP unhappy if the battery isn't completely charged, but the issue goes away as soon as the boat starts. AirJeff has a good solution, but it sounds like a lot of work.

[jhiestand]

Well, one thing I can do is trace the PP power/ground leads and do similar with the voltage gauge. There have been many mentions that all the instruments are daisy-chained and the ground isn't stout enough, so that's something I can check. That'll take some digging. I've seen a lot of people "solve" the same issue by simply running higher gauge +/- to the black box and I was hoping that'd do the trick.