When running the 16V24 or S16A AGM Series two post systems, we recommend that you resistor any components using the step-down voltage resistor if the component is not listed as 16 volt compatible by its manufacturer. We recommend that wiring in the car be no smaller than 16 gauge wire. Should you have a concern regarding wire size to a component, that component should be resistored.
**** The STEP DOWN RESISTOR is wired IN-LINE on the hot wire of the component(s) to be resistored. The unit is not to be grounded. The black wire is NOT a ground. We strongly suggest that if you are unsure as to whether a certain component is compatible with 16 volts, that you contact the manufacturer of that product for their professional opinion.