Correct Wiring Gauges

[Paul]

Hi Guys,

How do I determine the correct wire gauges if the car service manual doesn’t says so?,

I’m planning to do a rewire, wires too old and spaghetti already.

Buying a wiring harness may be next to impossible, because of the car being an old model already.

Nissan B12 5s manual, E13s.

Topic

[Mike]

Factory wiring diagrams normally indicate the gauges of wires in them. When I’m working on a job and need to patch the correct gauge wiring, my in-a-pinch tool is a insulation stripper tool that has individual (labeled) holes for each gauge and find whatever one fits the wire in question. The vast majority of car wiring, including older Nissans, is 18, 20, and 22 gauge stranded wire. The noticeably thicker wires are 16 gauge. 14 gauge and under (thicker yet) are usually reserved for battery, main ground, starter, and alternator wires.

This is the type of tool I’m talking about that has the sizes printed on it, one side denotes solid wire and the other stranded:

[asetoftools]

If you dont have a manual, but do have the fuses/fuseblock, you could determine the amperage of the circuit and length of the wires (ballpark), then use a wiring chart like this: http://www.driversdenabq.com/DIY_car_stereos.html

and simply rewire it based on the theory in the chart. It never hurts to use a lower gauge wire than was originally there! However be careful that if you do use lower gauge wire, that it still FITS in the conduits and such that you need to poke it through!

make sure its stranded wire, and for god sake COLOUR code things! dont use the same colour for every circut!!! you probably want to document it too this time. It might be easier to just get a dealers manual which would certainly have the colours and gauges.

[Paul]

may I ask what’s the call for this, I’ll search it up on Amazon and probably get my hands on it.

[Author]

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