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how to rewire the ignition on my 720?

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I have a 1980 datsun 720 with l20b (CA) and i recovered it from theft a while ago, finally got around to trying to repair it myself and i need help how to rewire the ignition


there are 4 wires that come from the harness that plug into the back of the ignition. 1 white and red wire, 1 white and black wire, and 2 plain white wires


i have managed to strip the wires and add electrical connectors to the tips (pic related)


now i just need to know where each wire leads to on the ignition

the ignition has 5 leads (3 on one side, 2 on the other)


and are labeled with B, S, A, IG, R and i dont know which wires go where, also there are only 4 wires and 5 leads so do i just leave one with nothing attached?


i have the service manual but for some reason i can't understand what it is trying to tell me since i'm not that great with electronics, maybe somebody on here is??

here are pictures.







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First you might want better connectors... something that is covered and insulates the exposed metal from touching...

Better yet slip some shrink wrap on and cover the terminal ends.... 

Ok with that out of the way....

You need to determine which white wire is the battery lead....


So white battery to the B terminal 

Other white to the IG terminal..

White and red to the A terminal 

White and black to the S terminal


I have no idea about the 5th terminal... just cover it just incase it has power... 

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Make sure you mark which White Wire has the 12 volts on it, I messed up a long time ago and put the 12 volts in the wrong place and couldn't figure out why I was only getting power to the ignition and nothing else.

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If at all possible, before you install the heat shrink, find an off colour, ie: usually there's black and red. Attach the red to 12v positive only and the rest with black. No more confusing which wire has constant power.

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