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2jzge na to t 76 280z wiring issues

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Keeping this separate from my build, to make it easier for someone searching to find if anyone has similar issues.


So in my build Im using a wiring specialties harness. Made life easier to just plug and play however it for sure didnt make my life easier because of my mistakes. So some details:


76 280z efi, was auto when it was made, transferred to manual. 

94 supra 2jzge na to t, 350z 6sp.



My issue begins with how do I wire up components like gauges, boost controller unit, AEM wideband unit, accessories and power in general?


So here is what I did:


I made my fusible link conversion to maxi fuses. I have that hooked up to positive on battery. I have another cable on positive to starter. I have my volt gauge wire hooked up to positive. Also have my relay for headlights to positive on battery. My headlights, signals and brakes work fine. 2jz need a cable from the alternator to the starter to recharge it. 


The negative terminal has the chassis, engine and headlight relay grounds. 


Now wiring specialties has a subharness thats for the fuses and relays. Has wires such as fan switch, reverse switch, a/c, oil press, CEL, coolant, speedo, tach, and  Now the important ones, Alt light, start signal, and ignition +. 


The start signal is hooked up to the back of the ignition cylinder BLACK with YELLOW wire.


I have hooked up alt light, ignition +, my speedhut gauges +, aem wideband + and profec controller + to the back of the ignition cylinder the WHITE with RED wire. Now thats where my problems start.


Seems to give me constant power with NO key in. Looking at the wiring diagram it seems like that wire is a good choice so im not sure whats happening? It also primes my fuel pump with no key, which im sure will be fixed with the correct wires. The diagram shows it stages from ACC, ON, START.


On a side note connecting my speed hut gauges the back light doesnt come on when the gauges were on. Im pretty sure I connected it to the wrong wire. Looking at the colored diagram should I hook them up to the RED with Blue wire? I think I connected it to the green with white on the tach which isnt good. 


High beam light comes on with low beam light and off at high. Connect that to the RED wire? I dont recall which one I connected it too but figured id ask.


I appreciate any help. Wiring isnt my strong suit but I do my best to understand it but this has me stumped since its a 12v switched ignition.

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Easiest way to solve the issue is going to be with a volt meter. First, disconnect the gauges from the power source you've chosen and with a volt meter test the wires you're targeting as a potential power source with the key in the off position, ACC, and on. Do the same for headlight switch for gauge light power.

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Slightly convoluted with all you have done. Maybe best to focus on one thing at a time.


For the ignition problem:

Off the top of my head, I thought white with red stripe thick gauge is constant power and the black with yellow stripe is ignition signal, aka ignition on. You might have hooked all that up to the wrong side of the ignition switch which would explain quite a bit, basically you shorted your circuit to bypass the switch. 


I would take a step back, unhook those wires for now and turn the key and see which wire becomes live when the switch is in ignition and start. You want to tap into that wire for the power signal. Ideally you are tapping into it for a signal and the power itself would be coming from a relay. My ignition signal comes through one wire and I have a relay box that distributes the power.


For gauges:

You usually have a couple connections, one is power for the gauge, another is the LED signal itself that you usually tie into the headlight signal so that it lights up when it is dark, unless we are talking about full LED gauges then you usually have a dim and not dim signal so that the LED's are visible during the day, but don't blind you at night. Easiest way would be to look at the back of the factory gauge, the same circuit lights up all the gauges, so that would be one wire, the gauges get their power from a common source so that would be the power wire and the factory gauges I think actually grounds through the metal dash for some of them so that one might not be visible, but pretty easy to address.

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Thanks guys! 


I figured the constant power was the white with red. So took the starter wire to the black and yellow, worked good. The rest of the wires I hooked up too black with white: thermo stat, override switch, wideband, boost controller, alt light, ignition + and speedhut gauges.


The gauges i havent started messing with yet. ill update on that later.

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