07 freightliner wiring


Well-Known Member
Wires on cb from truck are same color. Need to know which one is positive and which is negative.
easiest way since they are the same color, you will need a test light. ground one end, the other touch one of the wires, then turn on the key. it it lights up, it is the positive.

try same procedure on the other wire, if it does not light up, it is the negative.

sometimes, there will be marking on the wires, maybe faded out a bit, look further up the wire if you cannot see any markings at the end.