Aaargh! Electronics for the electrically challenged?

[Blown353]

The grounding problem could be it, what you have now is not adequate. You want a heavy gauge ground going from the battery to the engine block (4 gauge or heavier), another good ground from the battery to the body, and while redundant another good ground between the engine and the body and is a good idea. You should also run one between either the body/subframe or engine/subframe.

If that doesn't clear it up, my other guess is a bad alternator or a bad wire leading to the voltage sensing terminal on the alternator. The factory hooked the sense wire up to the horn relay, which was the main power take off point for the electrical system. It's always a good idea to hook up the sense wire to your main distribution block that way the alternator maintains the proper voltage at your distribution block, rather than just proper voltage at the output terminal.

Troy