Fuel Pump Power Question - GTS Zenki

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Fuel Pump Power Question - GTS Zenki

Postby Kitsunami » Fri Sep 21, 2018 7:37 am

Morning all!

I'm nearing completion on my swap, but I'm stumped on my fuel pump wiring. Two things to keep in mind: (1) I have a custom MSI pump for my setup on a stock SR5 tank (2), my rear harness is also a stock SR5 harness. I'd like to have the power spliced in from the Driver's side fuse panel, like it would be on a stock GTS, instead of running a wire all the way to the COR, but can anyone tell me specifically where the fuel pump gets its power on a GTS zenki dash harness?

I *suspect* that the correct lead is the one I've circled in the photo below, as it only gets 12V when the key is on position, but I'd like a second opinion if possible.


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Re: Fuel Pump Power Question - GTS Zenki

Postby jondee86 » Sat Sep 22, 2018 1:31 am

How are you planning to control the fuel pump ? On a GTS the COR supplies power
during cranking and after the door in the AFM has opened. The ECU has the ability to
shut the pump off (by de-energizing the COR) if the engine stalls after you hit a tree.

As a minimum you would want the COR output to control a relay switching a 12V fused
supply from any other source for the pump. Running a new wire for the pump would be
better than trying to pick up some other 30 year old wire in the harness that runs to
the rear.

I haven't read your build thread so my apologies if I'm talking out of turn :)

Cheers... jondee86
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Re: Fuel Pump Power Question - GTS Zenki

Postby DeadDuck » Sat Sep 22, 2018 9:27 am

I've done it two ways. 12 volts to the fuel pump from the battery, a relay that controls the ground for the fuel pump, and the 12 volt source you have pictured to turn the relay on and off. The second way is as stated above, but I added an inertia switch from a Ford Ranger to kill power to the pump if I was ever in an accident.

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Re: Fuel Pump Power Question - GTS Zenki

Postby UNLIMITED 86 » Sun Oct 07, 2018 9:44 am

If you're using the zenki dash harness, you have the COR (assuming it came with your harness) and its already wired correctly. All you have to do is redirect the pump power to your in-line pump.

Since it sounds like your mixing GTS dash with sr5 rear harnesses (zenki too?), I suggest you make sure they are compatible otherwise your project could literally go up in smoke. Just cuz they plug into eachother doesn't mean they're wired the same.
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