Talk:Rewiring a vehicle

one must realize that many times you will supply power to a circuit (ie; tail lights), and many times you will supply a ground, as the lights have power supplied directly to them. this is very common in courtesy lights that are grounded when the door switch is activated. also,some times you must use existing wires (as when they go from the dash, up the 'a' pillar, across the top, to a courtesy(interior)light. these are seldom removable if you have the headliner in place. use test device to be sure there are no shorts or 'opens' (broken wires). also, if you are changing from 6 to 12 volts (a very good idea), your new wire does not have to be as large as the original, as the current will only be 1/2 the original. This can be important when buying wire in several colors. you can often do 90% of the car with 14ga wire,or even 16ga! actually,a custom harness may often be cheaper, if you want to use factory color codes. also, if you use led lights, the current is minscule! and, they generate no heat! and boy, are they bright! Just a few thoughts from someone whose been there.

one must realize that many times you will supply power to a circuit (ie; tail lights), and many times you will supply a ground, as the lights have power supplied directly to them. this is very common in courtesy lights that are grounded when the door switch is activated. also,some times you must use existing wires (as when they go from the dash, up the 'a' pillar, across the top, to a courtesy(interior)light. these are seldom removable if you have the headliner in place. use test device to be sure there are no shorts or 'opens' (broken wires). also, if you are changing from 6 to 12 volts (a very good idea), your new wire does not have to be as large as the original, as the current will only be 1/2 the original. This can be important when buying wire in several colors. you can often do 90% of the car with 14ga wire,or even 16ga! actually,a custom harness may often be cheaper, if you want to use factory color codes. also, if you use led lights, the current is minscule! and, they generate no heat! and boy, are they bright! Just a few thoughts from someone whose been there.