I need some direction or input. I'm new to this forum and could use some knowledge , I put in a new cab dome light where the original was missing, I ran the blk wire overhead on driver side towards the headlight switch. Now I'm not sure what terminal to connect it to, it's a Universal Headlight Switch with Rheostat Dimmer: Batt, Aux, Head, Park or Tail. I'm thinking Batt but not sure? "Oh" I had my truck converted from 6v to 12v. EH
Not Batt unless you put a fuse in the wire to the dome light as close to Batt terminal as possible. Head will only have power when the headlights are on. Park will only have power when the parking lights (and not the headlights) are on. Tail will have power when the headlights or parking lights are on. So that leaves Aux. I'd get an inline fuse holder (either for a glass, AGC type fuse or a more modern fuse like shown below - either can be found at your FLAPS), connect one end to Aux and the other end to your new wire. You didn't say what kind of bulb is in the dome light. Find out and look up the power requirement for the bulb. Then get a fuse that is at least 25%, but no more than 100% higher rated. For example, if the current draw spec for you lamp is 3 amps, a 5 amp fuse would do.
