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Discussion Starter #1
I'm trying to find out the exact signals for the Fuel Pump ECU. I'm building this 2JZ setup into my MA7 and I need to know how to fake the Fuel pump ECU and how it works exactly. I know the FPE (fuel pump ECU) gets 12v through the EFI relay 2. The ECU signals the pump in two stages, 12v and 9v or something. I assume this is done with the FPC signal (violet-white). FPC should be Fuel pressure control or something. Or fuel pump control. Right? Now what I thought is that the "DI" signal (green) stands for some sort of 'main switch on/off'. Hence the pump not running when the key is at 'on' and the engine is not running nor starting.
Well, I checked with a multimeter and discovered the FPC signal does nothing and the DI signal is 0 when no current flows to the pump (pump disconnected) and +12v when the pump is connected. This is not exactly what I thought. Anyone got some information on this subject or possibly can do some testing. The Blue-Orange is +B and the blue red goes to the pump.
 
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The FPC signal is what tells the pump ECU to duty cycle the pump voltage to slow it down. It is a duty cycle control from the ECM to the pump ECU. The DI line is the diagnostic line telling the ECM the pump ECU is working properly. If you feed a constant 5 volts to the pump ECU FPC line, it will keep the pump voltage a constant 12volts. 50% duty cycle of the FPC signal will cut the output to the pump down to the low pump speed. Regardless, you really don't need the pump ECU for your pump. Give it a constant 12v from a relay and everything will work fine, just trigger the circuit opening relay on the car now with the line from the EFI relay. It doesn't sound like you are using the 2JZ ECM or you can just connect the wires like it was from the factory. Just know that the pump will not shut off or be controlled by the ECM in the event of a crash. Normally the ECM will not activate the pump if it does not have a crank speed signal.
 

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Discussion Starter #3
thnx for your answer, but I really don't want the pump to pump when the key is at 'on' and the engine is not running at all. So I was thinking of making some electronics for the fuel opening relay. I need some signal that tells that the engine is running and I thought to get that from where the fuel pump ECU used to be. Do you know what the range of the duty cycle is for the FP signal? Is it from 0% up to 100%? The last option would be using the fuel pump ECU as the controller for the fuel opening relay! That's easy. I cannot use the fuel pump ECU btw, as I have a walbro pump and that one doesn't like to get only 9 volts or so. It's a fulltime 12 v pump anyways.
 
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What engine management are you using and I will tell you what you need to do.
 

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Discussion Starter #5
I'm using the Stock 2JZ-GTE engine management (Jap spec). I'm using the MA7 (7M-GTE) fuel opening relay and a walbro (on/off) pump.

I need to convert the pulse signal you're talking about to a signal for keeping the fuel opening relay closed so that the pump flows the fuel. And the relay must be disengaged when the engine stalls.
 
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