Thread: Different voltage at meter and battery

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I understand voltage drop, but why all of a sudden and not at the time I initially wired it? Nothing has changed in the wiring since 1995. Also, why is the drop not proportional to the battery voltage? The battery voltage stays at 13.86v with the lights on, but the gauge reads 8v or so.

I suspect a grounding issue or that the internal regulator is at fault as suggested above, and will let this thread know as I learn more. There's not a bench-testing facility within 26 miles of me anymore (a one hour drive in this area) or I would have already confirmed or eliminated the regulator. I hate to just change parts until the problem goes away.

The AutoZone web site is filled with helpful test procedures, so that's my next step. The only problem I've found is that with our creations is that we have to interpret and adapt those standardized procedures to our particular cars.

Thanks for all of your comments.

I would first pull the battery and insure that it will hold a charge and that it does not have a weak and/or dead cell. I would then have the alternator and starter, including solenoid, checked to insure that neither has an internal short to ground. I would isolate all other components by pulling fuses to make sure that noting is grounded that's not supposed to be. It's then merely a matter of tracing the ignition/charging circuit looking for wires that could have chaffed and grounded.