Voltage drop at ballast resistor

Paladin06 said
* For your own education, measure the voltage across the battery while charging. (13.24 volts)
My cars stay on a trickle charger all the time.

* Measure Voltage at Battery Positive (13.04 volts) *, Alternator Output (Bat) (12.96 volts), and Bulkhead at Red Battery (12.88 volts),

Good. 13.24 Volts brings up the battery's surface charge. The reason the voltage goes down at each point you measured is probably entirely due to the surface charge dissipating.

Paladin06 said
Black Alt, (1.4 volts)

This must be a typo or a bad reading.

Paladin06 said
Blue Run. (0 volts)

As we expect. So far so good - except if that Alternator output connection reading is real - which the only way it could be is if its a loose connection and got worse when probed. Does that make sense? Everything in the main run should be at battery voltage.