How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by RckyMtnLegacy » Wed Jan 04, 2017 8:43 pm

Legacy777 wrote:Can you post the pin outs or if you got them from me or somewhere else, let me know which ones you're using and I'll take a look.

https://redirect.viglink.com/?format=go ... M%20UK.pdf

http://www.surrealmirage.com/vrg3/ecupins/
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 » Thu Jan 05, 2017 6:58 pm

RckyMtnLegacy wrote:
Legacy777 wrote:Check out my ECU I/O spreadsheet.

http://bbs.legacycentral.org/viewtopic.php?f=19&t=53822

B48 pin 21 is for the coolant temp sensor and shouldn't be tied into the MAP sensor ground.
I am still confused by this when the write up explains to do this:

MAP ground (B48-5 ; Red) :: Merge with B48-21. B48-5 is used for the stock JDM EJ20G cat efficiency EGT sensor. Not having an the stock EGT sensor has zero impact on how the ECU runs. The EJ20G harness combines the MAP sensor ground with all other sensor grounds at B48-21.
I went back and looked at my spreadsheet and the wiring diagrams and the coolant temp sensor does tie into the sensor grounds inside the ECU....so I'm not sure why I said it shouldn't be tied into the MAP sensor ground. Sorry about that, please disregard.
Josh

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 » Thu Jan 05, 2017 7:36 pm

RckyMtnLegacy wrote:Replaced the crank sensor wiring from the harness connector to the ECU. I have also printed out the USDM and JDM pinouts and am going through each terminal to match everything up. I would like to run a couple things by you and let me know if I need to move this to my build thread instead.

Are these the same thing just worded different? Left is USDM pinout and right is JDM pinout descriptions.
Please see below.

Self-Shutoff Control and POWER TO MAIN RELAY - Yes, based on the wiring they appear to be the same thing, just worded differently
IDLE SWITCH and TPS - Yes, based on the wiring they appear to be the same thing, just worded differently
IGNITION SWITCH and FUEL PUMP RELAY IGN - I can't find the connector B95 as it's called out in the table in the diagrams
POWER SUPPLY and MAIN RELAY IGN - I can't find this particular label in the table, which pin are you referring to?
BACK UP POWER SUPPLY and FUEL PUMP/IGN SWITCH - No, these are not the same. I'm going to have to look at these more to decipher things.

Other items I had questions with are:

I assume MAP on USDM pinout is considered BOOST PRESSURE in JDM pinout? - Yes, I agree.

What is TI MONITOR? USDM has one JDM does not - TI Monitor is some sort of factory diagnostic pin
Josh

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by RckyMtnLegacy » Thu Jan 05, 2017 8:07 pm

IGNITION SWITCH and FUEL PUMP RELAY IGN - I can't find the connector B95 as it's called out in the table in the diagrams
POWER SUPPLY and MAIN RELAY IGN - I can't find this particular label in the table, which pin are you referring to?B43 CONNECTOR TERMINAL 2 in EJ20G pinout
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by RckyMtnLegacy » Thu Jan 05, 2017 8:41 pm

And it's called MAIN RELAY IGNITION B48 pin 2 on USDM ECU
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by RckyMtnLegacy » Thu Jan 05, 2017 8:59 pm

Found b95 in center of page 18 near where it says Engine control module and I believe it's b12 Y
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 » Fri Jan 06, 2017 6:54 pm

Ok....I've got to take a step back on this.

There are two separate wiring diagrams in there, the JDM and UK. Which wiring diagrams are you using? I'm not quite sure how'd you be able to use a combination of both, but that seems like what is happening. If you can provide a little more guidance on what you're looking at, that'd be helpful.

Thanks
Josh

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by RckyMtnLegacy » Fri Jan 06, 2017 7:06 pm

Really the help I need is:

Do I just do the steps in the first page and the ECU should start this car? I am trying to trace every wire to make sure the 2C ECU I have will run my EJ20G. I am getting no spark at all but followed the steps to get each coil a wire directly from the ECU, each has 12v and grounded correctly.
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 » Sun Jan 08, 2017 10:07 pm

That unfortunately isn't something I can answer as I haven't done this work myself. I would assume that if the instructions state to do it a certain way and others have done it successfully it should be fine, however if yours is not working then yeah troubleshooting every wire is a good next step.
Josh

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by RckyMtnLegacy » Sat Jan 14, 2017 5:14 am

We are thinking the ECU is bad trying to Source One
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by RckyMtnLegacy » Sat Jan 21, 2017 9:25 pm

Got it going! Will have full explaination soon
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 » Fri Jan 27, 2017 8:24 pm

Awesome! Glad to hear it's working and looking forward to hearing what the resolution was.
Josh

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by RckyMtnLegacy » Sat Jan 28, 2017 2:35 am

Here is the main gist the crank sensor wiring was at fault. I had only one harness connector for the CS so I had to use what wiring was left of it. I bought 100ft of shielded 2 wire cable to bypass the harness wiring and go straight to the ECU. Still no start, cranked only. We checked all wiring and it seemed fine but could got no signal and injectors no pulse. From everything I could find and remembered the CS gets 5v reference from the ECU...but after a month of research I found out it doesn't which is good because we almost condemned the computer. The crank sensor only sends millivolts to the ECU. Once we found this out we went through the CS wiring and at the connector I made earlier I had used liquid electrical tape since it was so brittle. Come to find out liquid electrical tape has small bits of metal in it and when you need to send tiny volts any metal across the wires could cause signal to be disrupted. Once wires were fixed the car started, still has a rough idle and will die after a bit but it runs.
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 » Sun Jan 29, 2017 4:48 am

That is quite the detective work, congrats on figuring it out and getting the car started again.
Josh

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Pntaste4evr99 » Mon Jan 30, 2017 12:14 am

Just wanted to throw out there that I just finished my COP conversion and mainly thanks to this thread and a couple other bits of info around it was a success! Wanted to say thanks for all the ppl on here that put these posts on here for others to learn from(and not make the same mistakes) lol
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Sublimejoe » Wed Jun 28, 2017 4:09 am

Hey guys! About to attempt this soon and I was wondering if anyone knew where I could get some pigtails for the coils so I can plug directly in after I wire.

Thanks!
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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by RckyMtnLegacy » Wed Jun 28, 2017 6:15 am

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by lor » Sun Mar 03, 2019 7:22 pm

hello!

pleae help me!
i have '93 legacy (this is now a 2.0 legacy turbo)
this have an old style metal ignitor (http://www.anythingelectronic.co.nz/aen ... cts_id=348) edited
i have also the wrx coil on plug with the matching connectors
https://i356.photobucket.com/albums/oo1 ... jswr7d.jpg edited
the wires from the both side of ingnitor is connected correctly.
but when i turn the igniter to on.
it is allways 12v and! the ground in all the connecors of coils.
the 12v is in the connectors is ok but the ground not, when i think correct the ground is controlled trough the ecu.
now all of the coil connecors have 12v and ground.
while cranking the engine then sometimes (i hope in the correct time) it is break.


what is wrong?

maybe i need to put a not logic gate in the system?
Last edited by lor on Tue Apr 09, 2019 5:06 pm, edited 3 times in total.
lor from Hungary

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 » Thu Mar 07, 2019 6:35 pm

Hi Lor,

The links you provided don't work. It looks like they were copied and pasted and just the three dots showed up.

Can you give us a little background information on your problem. Are you trying to convert to the newer style coil on plug setup? Is this something that has worked on your Legacy before and now isn't or is it something you're trying to get to work.

Thanks
Josh

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by lor » Tue Apr 09, 2019 5:20 pm

Hello!

The links are edited, now they are working.

I have a BC5 legacy 2.0gl.
I made a swap with legacy turbo engine ecu harness ... (the legacy turbo in EU have the old style metal ignitor with coil on plug system, see last post from me)
Then i have modifiyed the ignition system with the new style coil on plug system (from one legcy twin turbo)
So the metal ignitor comes out and the old coil on plug also.
But the engine wont start!

I have measured a lot of thing with digital tester and i found a problem.
The problem shows this picture
https://i356.photobucket.com/albums/oo1 ... xgjbvh.jpg
At the ignition time i dont have an ignition signal.
Because it's look like negated.

Have somebody any suggestion?

May in put a not logic gate in the ignition system?

And this is the metal ignitor.
viewtopic.php?p=440123#p440123
lor from Hungary

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 » Tue Apr 09, 2019 6:45 pm

Hi Lor,

To confirm your wiring, do you have the signal wire for each ignition pin out at the ECU going directly to the coil on plug, the power wire from the coil on plug going to an ignition switched 12v source of power, and it appears the ground is grounded through the bolt holding the COP to the valve cover?

If all that is correct it should work.

Based on your drawing, I believe you're saying you're getting a negative voltage vs. a positive voltage and the coils are not triggering. I would think the only way to get that would be to have something wired backwards. Are you 100% sure you have the wiring correct?


PS: What part of Hungary are you from?
Josh

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 » Wed Apr 10, 2019 2:45 am

Lor,

I was thinking about this again and your picture shows a rising edge trigger vs. a falling edge trigger (Disregard my comment about the negative voltage above). So instead of going from 0v to 12v it's going from 12v to 0v. Is that correct?

Is the ECU, crank/cam sensors, and crank/cam wheels/pullies the same as before? If that's all the same and all you have changed is the igniter & coil pack setup I'm a little confused as the information from my Link ECU indicates most coil packs are setup for falling spark edge. It's the same for the newer WRX's (V7), they are setup as a "falling" spark edge.

Where did you take your oscilloscope readings?

Here is the note from the help file in the Link ECU software:

Spark Edge sets the edge of the ignition signal that causes the coil to fire a spark.

A Falling Spark Edge will start the coil charging when the ignition signal goes high and fire the spark when the
signal goes back low (FALLS from high to low) . On an oscilloscope this signal would be normally low with a high
pulse equal to the length of the current dwell time.

A Rising Spark Edge will start the coil charging when the ignition signal goes low and fire the spark when the
signal goes back high (RISES from low to high). On an oscilloscope this signal would be normally high with a low
pulse equal to the length of the current dwell time.
Josh

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by lor » Wed Apr 10, 2019 11:18 am

I made the testing at the connector B156 (viewtopic.php?p=440123#p440123) without the ignitor.
I was thinking about this again and your picture shows a rising edge trigger vs. a falling edge trigger (Disregard my comment about the negative voltage above). So instead of going from 0v to 12v it's going from 12v to 0v. Is that correct?
Yes!
When i think correct at the B156 connector the signal must go from 0V to 12V (while ignition) to open the transistor in the original ignitor.
When the transistor open then can flow the current so give the spark.
And as i know this signal is enough for the new style coil on plug system so i doesnt need to use the old ignitor (what is in fact is an amplifier, just the name is ignitor)
Where did you take your oscilloscope readings?
I made it whit a small bulb what you can find in the dashboard.
But with this you can see the signal is ON on most of the time.


As i remeber i tested earlier this signal and was ok.
Then a lot of time and thing changed.
But the ecu loom and crank and cam sensors are the same.

One times the engine was running, then one month after doesnt start.
I need to repared the cam angle sensor wire, but after wont start teh engine.
Then i need to change the head gasket beacuse it was thin and changed a tranny to blob sti spec-c tranny 8-), and i put the new style coil on plug from a legacy gtb.
And here we are.

I think maybe in the ignitor integrated one not logical gate? Soe the signal is nageted?
On the weekend i will test it.
And maybe i make a small device that will negated the signal.


Two site from the service manual:
Image

Image


I live in Miskolc, this is the 2. or 3. biggest city in Hungary.
https://en.wikipedia.org/wiki/Miskolc
Near by the mountain Bükk, so we can drive our subarus when it is work. :-)
lor from Hungary

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by Legacy777 » Wed Apr 10, 2019 6:06 pm

Hi Lor,

Just to make sure I have this correct, the engine was running and then a month later it didn't run. You repaired the cam sensor wiring. Did the engine run after you repaired the cam sensor wiring? If the engine never ran after you repaired the cam sensor wiring I would go back to that. The crank & cam sensor wiring doesn't take too well to be repaired due to the low voltages involved, plus the shielding. Do you have a used or spare cam sensor you could use for testing purposes? Also, you could try unplugging the cam sensor completely and see if the engine runs at all.

Is there anyway you can put the old igniter & coils in to test things to see if the engine will run on them? It's possible that Subaru changed the ignition configuration (falling vs. rising) just for the twin turbo Legacy, but I have my doubts. If you can easily make something that will change the trigger setup from falling to rising I suppose you could test that as well.

When I'm troubleshooting I try to go back to a known working condition if at all possible and then introduce one change at a time. When you do some more testing this weekend let us know what you find out.


My wife is Hungarian. She grew up in Budapest. We were there last year. We went to see her grandmother in a small town about an hour outside of the city, but I don't recall where :)
Josh

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Re: How-To: Convert To GD WRX Coil On Plug w/EJ20G ECU

Post by lor » Wed Apr 10, 2019 7:02 pm

Did the engine run after you repaired the cam sensor wiring?
No.
The crank & cam sensor wiring doesn't take too well to be repaired due to the low voltages involved, plus the shielding.
I repared the wire and the shield also, with a thin aluminium foil. 8-)

As i know i have a spare sensor maybe this is the same plugged version. (sensor wire plug)
Also, you could try unplugging the cam sensor completely and see if the engine runs at all.
Without the sensor they will run?

When the legacy gtb is falling not rising ok but the ecu is my legacy turbo.
And the signal is biggest problem, i think.
On the weekend i test the old ignitor what type of signal comes out, i have one another Z4 type ecu this will i test also.
May be i can soldering back the old coil.
OK, I make a lot of test.
My wife is Hungarian.
In this case say the Hungarian people:
"The world is small!" :-)
Ok you are biased.
What do you mean the hungarian girl/woman are realy beautifull?

Thanks for the help!
lor from Hungary

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