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Phizinza

EJ in EA, wiring, Neutral switch, ?

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Ok. So I'm taking out more unnecessary wiring, mainly the gearbox stuff from the EJ loom.

 

I'm at a bit of a dead end, not sure what to do. I see that the two plugs to make the cell light are on pins 12 and 13 on the

second smallest ECU plug. And I see these are related to the neutral sensor on the EJ gearbox. Because I'm running the back half of a FT4WD gearbox I don't have that sensor. Now on the smallest ECU plug there is a wiring in pin 10 that goes directly to the gearbox. This is the ECU's way to tell if it is in neutral.

So I am figuring, The CEL light only displays when in neutral. So this pin-10 wiring would need to be connected to earth, but only when you want to read the codes. But my worry is, when shifting gear, does the ECU want to know when you hit neutral. Or does something else need to know that? Would it matter if this neutral wiring was just disconnected until I switch a switch which allows me to read the CEL light.

Another thing, is the CEL light normally connect to the reversing lights? Cos there is a wire or two heading from the "memory" or "test" (pin 12 or 13 on the second smallest plug) to the gearbox.

 

Cheers for the help. Only a few more wires to deal with and then the loom goes back in that plasic cover stuff :)

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as far as I can tell the 2 pins you speak of have nothing to do with the trans in any way. they just go straight to the test and read mode connectors. if one of those wires are grounded, it activates the respective mode.

 

I believe the neutral switch CEL comes on if it remains in either position for an abnormal length of time. on EA cars, the switch is on the clutch pedal...so you could still wire it in there if you want.

 

the neutral switch doesn't effect reading the codes. but if that wire is not hooked up to the neutral switch, it will throw a code.

 

 

here's a simplified diagram of that section. I've labeled the 3 pins you mentioned....and the big circled "A" eventually gets to an engine ground.

92LegacyEngineWiring.jpg

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On my loom, the two plugs you plug next to the ECU that you plug in to read the codes have a black wit hred wire heading off of them going into the gearbox plug I think which looks like it goes the the neutral switch. There is also the other wire that is the other end of the neutral switch which looks like it heads to pin 10 on what you call plug C. This is orange on my loom, but it isn't suppose to be on the diagram I have. Hey, it's australia, so I expect that.

 

I am going to connect the wires on the two plugs to another black with red wire (which is ground.) But I'm still not sure what to do with the neutral switch (pin-10/orange) wire. My clutch pedal doesn't have a switch on it. Can I just hook it to a switch I can manually switch when wanting to read the codes?

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yep, the black wire with the red stripe is just a ground. they just share the same ground, but are completely separate circuits. the functionality of the neutral switch has no effect on your ability to read the codes. (I don't have mine hooked up....I can pull codes just fine....one of them is just for the neutral switch...).

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Ok, cheers, I will leave the neutral switch wire under my dash not connected.

 

One other wire though. Is it important to hook the ECU's radiator control wire to the fan relay, or should I just leave this wire out and use the original thermoswitch and radiator fan relay blah blah blah?

 

I'm putting the cover stuff back on the loom and I just ran out of electrical wire. I'll go get some tomorrow. Then I'll install the loom. I already figured out where I will route it in my RHD Brat.

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the rad wiring is your choice.Mine is hooked up to the ea sensor.Most of my mates have a permanent fan on ,brumbies and ea's,with a overide for off.From memory the ej ecu and the standard thermo switch turn on at the same temp.

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Sweet, thanks guys. I'll cut that wire out.

 

I don't like constant fan noise, I prefer it only cooling when at optimal temp. That's why I took my clutch fan off my EA81 ,those clutch fans make the worst noise.

 

I have all the interior wiring in place, just need to hook up the gauges and loom power now.

And then tape up some of the hood loom and route it around. I'll have pictures and all that in my other thread within a couple of days.

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