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Discussion Starter · #1 ·
Alright, so after the swap I have had nothing but electrical problems with my car. My first ECU crapped out so im now on ECU #2.

First problem, I didnt have the +B switched power to my ecu, but the first ECU ran fine w/o it and even had switched power?...
:1poke:

ECU #2 required me to wire in the missing +B. After doing so it worked flawlessly until my batterie died from sitting for for so long. So Today I picked up an Optima, hooked it up and it started rite up but died about 20 seconds later. The weird part is that it works if I jump power to the ECU. So basically I lost switched power AGAIN...

My question is, why am I now not getting any power off the +B? All the wire is solid from the ECU to the plug under the fuse box and the fuses are all good. Im just not getting any switching from the switched power, what am I missing?? Did the batt do this?

What can I do short of hard wiring and not having switched power to the ECU? Can someone give me an idiots guide to getting switched power to the ECU?

Mike
 

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Discussion Starter · #5 ·
Ok, so i went out and tryed starting it this morning and to my shock it started rite up.....But then died about 10 seconds later with no switched power, again....

Is this a Ground issue? Is the batterie causing all my problems?
 

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I have a 92 running the 1jz from a 92 as well. My car is a manual and I can check the big fat plug near the ecu to make sure you have them in the right slots? This will be later in the afternoon though..
 

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Discussion Starter · #8 ·
I know its a problem with my switched power to the ECU...I just have no idea what I can do to fix it.

Today It started once and run for about 2 mins before I shut it off, and after that it would not start again.

Sometimes it works...most of the time it doesnt. And it all started when I put the new batterie in.
 
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Your battery might have moved something around at the fuse block by your battery. Take your battery out and check your fuse block location for poorly soldered or insulated wires.

I also agree with the fuel circuit issue. There is a FC fuel cut relay that the ecu runs if it sends a FC signal no more fuel after a couple seconds so if you constantly dont have a +B your ecu might be shunting it because the missing 12 volts

+B taps off of your ([EA2] connector pin 5) Main EFI & Main EFI Relay circuit.
It also feed power to your injectors VSV and a ton of other stuff it sounds like to me you extended the harness & might have a weak solder joint or butsplice but check the fuse block by the battery to the EA2 connector.
 

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have you checked your battery, i know when my battery started to go out i had the same issue
 
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