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bratboy1

EJ swap wiring harness question

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Hey everyone... I may have messed up here and I am looking for some help. When I was pulling the harness from the donor car, I was not to knowledgable about what every connector was and I didn't label them accordingly, just the ones I knew. I am currently stripping my harness, and the only thing I have cut out so far is the cruise control. I have a bunch of pics and if anyone could help me identify some I would appreciate it a lot! I have numbered the connectors in questions, if there are more later on I can always upload more. I will also comment with some due to file size restrictions. Thanks!!

4-2.png

7-2.png

11-2.png

12-2.png

3-2.png

Edited by bratboy1

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More pics here:

 

I know 11 went to the clutch but when swapping the ej22 into the brat is it necessary? 

13-2.png

8-2.png

14-2.png

6-2.png

Edited by bratboy1

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Is this the ej harness, or the older car getting the swap?

 

I wouldn't attempt this without the FSMs for both cars, or at least  copies of the relevant pages. 

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21 = fuel pump relay. 22 doesn’t look familiar. 

8 = igniter. 

11 will be clutch and brake switches for cruise control

The others I don’t know. 

The best way to do it is to unwrap the wiring, then trace all wiring from the ECU and tape these wires together as you fish them out from any unwanted wires. 

Once you’ve got all of these wires taped, find where any tee off to other things and what they’re for - eg: fuel pump relay or sensors on engine. 

Anything you don’t need (once correctly identified!), cut and remove from the loom. 

You should end up with: 

- ignition power

- permanent power

- backup power

- starter wire (for ECU to richen the mixture for cold starts, references the start wire to the starter motor)

- fuel pump wire 

- temp and oil light wires (use the EA wiring for this). 

- vehicle speed sensor wiring

It’s best to have the wiring diagram to get your head around it. The Haynes manual has a good diagram of the ECU pinout with wire colours that’s generally easier to read than the FSM wiring diagrams. 

Put a fuse panel between those power wires including the starter reference wire and the EA loom. You will only need the vehicle speed sensor wire to tap into your factory L series loom. If MY another vehicle speed sensor source needs to be made. 

Cheers 

Bennie

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Feel your pain.... my first and only EJ donor got everything pulled, nothing identified, to rely on diagrams later.

Diagrams plural. For my donor 99 Impreza there is no single ecu pinout, just lots of little single circuit diagrams to piece together

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The only wiring diagram you really need is the ECU pinout. 

The main power relay diagram can be useful to actually (for your first cut down), but really the big yellow wire is power and the little yellow with a stripe (from memory but can’t remember the strep colour). The large black trace red wire is fuel pump power wire. 

Cheers 

Bennie

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9 hours ago, DaveT said:

Is this the ej harness, or the older car getting the swap?

 

I wouldn't attempt this without the FSMs for both cars, or at least  copies of the relevant pages. 

This is the EJ harness yea. I guess my question would rather be what connectors do i NEED? Here is a reference that I was using but I was not sure if it was complete or if I needed anything else:https://www.busaru.com/subaruvanagon/wiringharness

This guy is putting the ej in a VW so I was not sure if it was exactly the same, I am sure it is similar. I know I need things like the MAF, O2 sensor, etc. but I was unsure of what was the bare minimum. Thanks

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3 hours ago, el_freddo said:

 

9 hours ago, el_freddo said:

21 = fuel pump relay. 22 doesn’t look familiar. 

8 = igniter. 

11 will be clutch and brake switches for cruise control

The others I don’t know. 

The best way to do it is to unwrap the wiring, then trace all wiring from the ECU and tape these wires together as you fish them out from any unwanted wires. 

Once you’ve got all of these wires taped, find where any tee off to other things and what they’re for - eg: fuel pump relay or sensors on engine. 

 Anything you don’t need (once correctly identified!), cut and remove from the loom. 

You should end up with: 

 - ignition power

- permanent power

- backup power

- starter wire (for ECU to richen the mixture for cold starts, references the start wire to the starter motor)

 - fuel pump wire 

- temp and oil light wires (use the EA wiring for this). 

- vehicle speed sensor wiring

 It’s best to have the wiring diagram to get your head around it. The Haynes manual has a good diagram of the ECU pinout with wire colours that’s generally easier to read than the FSM wiring diagrams. 

 Put a fuse panel between those power wires including the starter reference wire and the EA loom. You will only need the vehicle speed sensor wire to tap into your factory L series loom. If MY another vehicle speed sensor source needs to be made. 

Cheers 

Bennie

So what I did for the cruise control is snipped the wires at the unit, followed them back as far as possible, and cut them off there. Those were the only ones I knew for sure I didn't need on the harness. This is from a 91 legacy btw. For instance do I need #11? That is my problem I actually dont really know what I need and don't need, I was going to include what this guy has here:  https://www.busaru.com/subaruvanagon/wiringharness

I can identify the connectors in that guys post, but I cannot really identify any others, so I was worried about cutting out something I really need lol. I am sorry if this post is vague or not really easy to work with, I am VERY new to all this and feeling a bit overwhelmed which I am sure is normal. Also i found this on the wayback machine: https://web.archive.org/web/20111012163255/https://www.shoptalkforums.com/viewtopic.php?f=28&t=136053 which has been a bit helpful. The two references that I just linked have different things they keep, but neither is swapping the ej in a 82 brat like I am so that is where I was getting lost. 

 

Thanks for all the help I appreciate it.

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6 hours ago, Steptoe said:

Feel your pain.... my first and only EJ donor got everything pulled, nothing identified, to rely on diagrams later.

Diagrams plural. For my donor 99 Impreza there is no single ecu pinout, just lots of little single circuit diagrams to piece together

Yeah and mine is even stripped of the shielding and tape so its a big jumble of wires at the moment! Thanks for the help!

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Ooh... you definitely want the shielding. This does not need to be removed in the cut down process. 

Tape removal is all good. Knowing what each plug is or having the mating plug is not always necessary. You just need the plugs and wiring to the engine harness, the igniter, air flow metre, O2 sensor, knock sensor, and the cam and crank sensors. And the ECU of course! 

It’s normal to be overwhelmed with your first cut down! 

First link looks pretty good. Second link, I don’t like how they’ve cut up the WHOLE loom to then piece it back together. 

You need numbchux’s conversion guide: 

 this is where you need to be looking. It’s specific to the conversion into an EA platform. 

I hope that helps. 

Cheers 

Bennie

 

 

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2 hours ago, el_freddo said:

Ooh... you definitely want the shielding. This does not need to be removed in the cut down process. 

Tape removal is all good. Knowing what each plug is or having the mating plug is not always necessary. You just need the plugs and wiring to the engine harness, the igniter, air flow metre, O2 sensor, knock sensor, and the cam and crank sensors. And the ECU of course! 

It’s normal to be overwhelmed with your first cut down! 

First link looks pretty good. Second link, I don’t like how they’ve cut up the WHOLE loom to then piece it back together. 

You need numbchux’s conversion guide: 



 this is where you need to be looking. It’s specific to the conversion into an EA platform. 

I hope that helps. 

Cheers 

Bennie

 

 

Yeah I was not about to cut the harness up like that lol....  I kept the shielding and thats all going to go back on after the harness is cut down. I will take a look at the numbchux guide and god from there. Thanks for the help! If I have anything else do you mind if I message you?  I appreciate it.

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Ah, by shielding you mean the plastic conduit stuff. I am talking about the metal shielding on the sensor wiring - it’s under a grey wrap/tube. Keep that stuff there, do not remove! 

No worries about messaging ;) 

Cheers 

Bennie

  • Thanks 1

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12, 13 & 14 look like the connectors that go to the engine bay fuse box. I'd definitely grab a copy of the ecu wiring diagram and follow that. 

Have you got the ecu number? We might be able to source the correct ecu pinout from that number.

Edited by STi 22B
Added info

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3 hours ago, STi 22B said:

12, 13 & 14 look like the connectors that go to the engine bay fuse box. I'd definitely grab a copy of the ecu wiring diagram and follow that. 

Have you got the ecu number? We might be able to source the correct ecu pinout from that number.

I can get it tomorrow mate! Its from a 1991 legacy. Let me take a look tomorrow, what number exactly am I looking for? Thanks!

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On 10/9/2019 at 7:24 PM, el_freddo said:

The only wiring diagram you really need is the ECU pinout. 

The main power relay diagram can be useful to actually (for your first cut down), but really the big yellow wire is power and the little yellow with a stripe (from memory but can’t remember the strep colour). The large black trace red wire is fuel pump power wire. 

Cheers 

Bennie

No ecu pinout in the Subaru manuals at my dealers...I was expecting to find just like the EA82 manuals

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11 hours ago, bratboy1 said:

I can get it tomorrow mate! Its from a 1991 legacy. Let me take a look tomorrow, what number exactly am I looking for? Thanks!

Sorry don't have my own photo for you but this is one I've found on the web to give you an idea of the numbers needed. Also can you please tell us if it has 3 or 4 yellow connectors.

Kabelbaum-EJ22-136-PS-Detail-ECU-mit-Spinne-fertig.jpg

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34 minutes ago, STi 22B said:

Sorry don't have my own photo for you but this is one I've found on the web to give you an idea of the numbers needed. Also can you please tell us if it has 3 or 4 yellow connectors.

Kabelbaum-EJ22-136-PS-Detail-ECU-mit-Spinne-fertig.jpg

Dude that pic is great! And its got 4 yellow connectors into the ecu. Are those all the connectors I need?

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8 hours ago, bratboy1 said:

Dude that pic is great! And its got 4 yellow connectors into the ecu. Are those all the connectors I need?

No probs mate, it's only a guide to show you what the ecu numbers look like. I'll need your ecu number to get the correct wiring details for your loom. 4 yellow plugs only gives me half the info, which it's gen1 legacy but I'll need the number to determine if it's series 1 or 2. If you could post up a picture of your ecu, we should be able to help you out. As for your question, nah bud, there is a lot more needed. My best suggestion is to nail the loom (not through the wiring of course) and then remove all of the black convoluted tubing to expose all the wiring. 

Here are some pics of one loom we did many years ago

TheStart1.jpg

ECUHarnessCutDown.jpg

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31 minutes ago, STi 22B said:

No probs mate, it's only a guide to show you what the ecu numbers look like. I'll need your ecu number to get the correct wiring details for your loom. 4 yellow plugs only gives me half the info, which it's gen1 legacy but I'll need the number to determine if it's series 1 or 2. If you could post up a picture of your ecu, we should be able to help you out. As for your question, nah bud, there is a lot more needed. My best suggestion is to nail the loom (not through the wiring of course) and then remove all of the black convoluted tubing to expose all the wiring. 

 Here are some pics of one loom we did many years ago

TheStart1.jpg

ECUHarnessCutDown.jpg

Cheers mate I appreciate all the help! Let me know if this is okay or not please. 

IMG_6201.jpg

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9 minutes ago, bratboy1 said:

Cheers mate I appreciate all the help! Let me know if this is okay or not please. 

Looks perfect. It's from a gen1 ser1 legacy. I will dig up the wiring diagram and let you know.

  • Thanks 1

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1 minute ago, STi 22B said:

Looks perfect. It's from a gen1 ser1 legacy. I will dig up the wiring diagram and let you know.

Thank you!

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On 10/10/2019 at 9:55 PM, Steptoe said:

No ecu pinout in the Subaru manuals at my dealers...I was expecting to find just like the EA82 manuals

You need to look for the FSM. They won’t show you these at the dealership. 

Cheers 

Bennie

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On 10/11/2019 at 10:56 PM, el_freddo said:

You need to look for the FSM. They won’t show you these at the dealership. 

Cheers 

Bennie

Factory Shop Manuals ? In the Blue plastic binders?

I was in Fuji heaven in the store room Bennie - nothing but these things. Picture book shelves about six foot wide, five foot high, crammed with these folders ! Shh...nobody let me in there, just had to freeze as Dealer Principal stuck his nose in there , switched the light on to find me with my micro camera and head torch :)

if you find a pinout for entire ecu please yell out !

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@Steptoe - tried these sites? 

https://www.allcarmanuals.com/factory-service-manual-48-Subaru-Impreza-WRX-GC.html 

This is another good one from memory: 

https://workshop-manuals.com/subaru/ 

Or find an old Haynes manual, they actually have a good pinout for the ECU - at least the one in the liberty manual is good, if that’s anything to go by it’ll be the same for the impreza one.

Cheers 

Bennie

  • Haha 1

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On 10/13/2019 at 10:32 AM, el_freddo said:

@Steptoe - tried these sites? 

https://www.allcarmanuals.com/factory-service-manual-48-Subaru-Impreza-WRX-GC.html 

This is another good one from memory: 

https://workshop-manuals.com/subaru/ 

Or find an old Haynes manual, they actually have a good pinout for the ECU - at least the one in the liberty manual is good, if that’s anything to go by it’ll be the same for the impreza one.

Cheers 

Bennie

Allcarmanuals site does not list 2.0 Bennie

I wonder if we can rely on LHD market ECU diagrams anyway ????

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