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obk25xt

EJ swap CEL help....

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Figured I'd start a new thread in an appropriate forum for this...

 

The harness/ECU both came from the same car. 1995 Legacy, auto.

They were stripped and installed by a VERY knowledgeable board member with plenty of experience, who is also VERY busy running his new business. I have the skills and abilities to handle this with the proper advice/direction.

 

I am getting codes for no EGR signal, no communication with the TCU, and cooling fan relay failure. I believe I have grounded the correct pin (81). I can get pictures if necessary. I really would like to get the CEL to stay off, the car runs FANTASTIC, I have no issues with drivability. After I grounded the pin, the car starts hard when it is dead cold, like after sitting overnight, it never had this issue before. This may seem like a lot of little bits of info, it is kinda all bouncing around between my ears so I am trying to get it out in a somewhat organized manner. There is a little background in the wanted forum, that is where this started.....

 

Please read: http://www.ultimatesubaru.org/forum/topic/137382-wtb-1995-legacy-5mt-ecu/

 

And help!

 

Thank you,

 

Spencer

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The codes are:

 

P1500, P1702, & P0403....

 

If that is any help.....

 

Also, on the plug going into the ECU, there are no wires going to pins 82-83, which according to the pinouts I've read should be vehicle speed sensor 2 (83), and neutral position switch (82).

Edited by obk25xt

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After looking at the diagrams posted on the previous post, I will send you what I have.

 

it will not let me up load .docx files so I will send you them in an email.

I  will include the Trouble Code trouble shooting guide for the ones you listed.

 

Ben

 

 

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Be careful.

 

95 Lego uses an ECU with the same connector as later 96-98,99, but with a completely different pin arrangement.

 

You must make sure you use only 95 wiring diagrahms, and if you ever need another ECU, it must be for a 95.  Kinduv a bummer that you used that harness/ECU.....It's the one model I ussually tell people NOT to use as an EJ donor swap.(not the electronics anyhow. 95 engines are fine just use a 90-94 or a 96-98 harness/ECU/Intake.

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Be careful. 95 Lego uses an ECU with the same connector as later 96-98,99, but with a completely different pin arrangement. You must make sure you use only 95 wiring diagrahms, and if you ever need another ECU, it must be for a 95.  Kinduv a bummer that you used that harness/ECU.....It's the one model I ussually tell people NOT to use as an EJ donor swap.(not the electronics anyhow. 95 engines are fine just use a 90-94 or a 96-98 harness/ECU/Intake.

Yeah I'm aware of this. I actually thought is WAS a 1996, it was labeled a 96 in the p&p yard and in the door jam. Wasn't til the swap was done I learned it was actually a 1995 harness. Musta been on the cusp of the model changes I dunno. Regardless, this is where I am now. And I am going to deal with the issue. I Would put a different plug on the harness with the 96-99 pin arrangement, but I'm sure that would be a major project for me.

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Yeah I'm aware of this. I actually thought is WAS a 1996, it was labeled a 96 in the p&p yard and in the door jam. Wasn't til the swap was done I learned it was actually a 1995 harness. Musta been on the cusp of the model changes I dunno. Regardless, this is where I am now. And I am going to deal with the issue. I Would put a different plug on the harness with the 96-99 pin arrangement, but I'm sure that would be a major project for me.

If you've got the proper 95 diagrahm, and know to user that it really isn't an issue.  ECU's seldom fail, so needing another once your fully installed, is unlikely.

 

So, one at a time.

 

Is there an EGR vavle on teh engine?  or just blcoked off.

 

Do you have a Fan relay installed?  Is the ECU triggering your electric fan/s?

 

ECU is from Auto car, it want's to see a live TCU on that input circuit.  I am not sure if that ECU can be tripped to Manual mode.  If it can, you will need to add a pin for the missing Nuetral switch wire.

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If you've got the proper 95 diagrahm, and know to user that it really isn't an issue.  ECU's seldom fail, so needing another once your fully installed, is unlikely.

 

So, one at a time.

 

Is there an EGR vavle on teh engine?  or just blcoked off.

 

Do you have a Fan relay installed?  Is the ECU triggering your electric fan/s?

 

ECU is from Auto car, it want's to see a live TCU on that input circuit.  I am not sure if that ECU can be tripped to Manual mode.  If it can, you will need to add a pin for the missing Nuetral switch wire.

 

No EGR on the intake manifold, and the head isn't tapped for it either. I DO have an EGR manifold, but it has been cannibalized.

 

Currently I am using the EA thermoswitch in the stock radiator. I will likely just wire in a dummy relay to satsify the ECU.

 

How do I add a pin?! Sounds technical. It can't be as easy as sticking a piece of wire in the hole. I am assuming I would be opening the ECU case and soldering something, correct? I can do this, I just want to be guided accordingly..... 

Edited by obk25xt

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No EGR on the intake manifold, and the head isn't tapped for it either. I DO have an EGR manifold, but it has been cannibalized.

 

Currently I am using the EA thermoswitch in the stock radiator. I will likely just wire in a dummy relay to satsify the ECU.

 

How do I add a pin?! Sounds technical. It can't be as easy as sticking a piece of wire in the hole. I am assuming I would be opening the ECU case and soldering something, correct? I can do this, I just want to be guided accordingly..... 

 

So, your gonna have an EGR code.  No EGR with an EGR ECU = CEL.......common on 2.5-2.2 swaps when EGR isn't used.  No biggy.

 

EA thermoswitch?  I would ditch that and let the ECU control the relay.  You could tie the thermoswitch in as a backup trigger for the relay.  But it isn't nessecary.  The EJ fan control works great.  I trust it more than the thermoswitches which I've seen fail numerous times. 

 

The pin should be on the ECU....just needs a wire in the connector to attach to it.  If there is no pin there on the ECU, then you probably are gonna have to live with that code too.

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The EJ ECU fan control is pretty nice.  I have this wired up along with a higher temp thermoswitch.  The ECU fan control works when the engine is running, and on hot days the thermoswitch will kick in after then engine is shut off to take care of heat soak.

 

You might get rid of the EGR code by using a dummy resistor.

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So, your gonna have an EGR code.  No EGR with an EGR ECU = CEL.......common on 2.5-2.2 swaps when EGR isn't used.  No biggy. EA thermoswitch?  I would ditch that and let the ECU control the relay.  You could tie the thermoswitch in as a backup trigger for the relay.  But it isn't nessecary.  The EJ fan control works great.  I trust it more than the thermoswitches which I've seen fail numerous times.  The pin should be on the ECU....just needs a wire in the connector to attach to it.  If there is no pin there on the ECU, then you probably are gonna have to live with that code too.

There is a way around the EGR with the proper manifold and some creative plumbing according to the link in the thread I have in the wanted forum.

 

And yeah, there IS a pin in the ECU, I remember seeing it now that I think about it. So I am adding a wire there, and where am I running this wire to?

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So, your gonna have an EGR code.  No EGR with an EGR ECU = CEL.......common on 2.5-2.2 swaps when EGR isn't used.  No biggy.

No, this is wrong. There is no egr vs non egr ECU or auto vs Manual ECU. They are all the same computer. There is a pin in the ECU connector that needs a wire going to ground to tell the ECU it is in a manual transmission car. With that wire grounded, the ECU knows that there is no TCU to talk to and no EGR to manage because no M/T cars had EGR. Figure out which pin that is, ground it, and that cures two of your codes.

 

I would use the cooling fan control. It works well and if the engine coolant temp sensor fails, the ECU failsafes to running the fans continuously.

 

Do you have a neutral switch and a clutch switch hooked up? The ECU will want to see those if it's a M/T. WIthout those you get stalling if you coast up to a stoplight and push the clutch in because it's still in decel fuel cut and doesn't get the pedal switch warning that it needs to start idling the engine.

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So I am getting mixed messages:

The MT/AT identification pin, some people say that it needs to be grounded for MT mode.

http://www.surrealmirage.com/subaru/swap/electrical.html#ecu : says that its not grounded for MT mode.

 

 

 

 

 

Found the answer:   This is the Pin (50) that needs to be grounded for manual mode.  

post-33-0-98469100-1367143193_thumb.jpg

Edited by SkankinPickle

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P1500:  Use this to hook up the fan;)

post-33-0-30336700-1367143855_thumb.jpg

The main fan relay is in the fuse box "F/B" inside the car behind the kick panel if the legacy did not have A/C.  

Here is the main-power-routing-diagram that shows how the Main-fan-relay (this would be the secondary fan relay if the car has A/C, and is labeled in diagram on pg. 2) 

post-33-0-12879200-1367143894_thumb.jpgpost-33-0-09169600-1367143898_thumb.jpg

This is how you want to set up your relay to control your cooling fan with your ECU.

Edited by SkankinPickle

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Do you have a neutral switch and a clutch switch hooked up? The ECU will want to see those if it's a M/T. WIthout those you get stalling if you coast up to a stoplight and push the clutch in because it's still in decel fuel cut and doesn't get the pedal switch warning that it needs to start idling the engine.

Maybe this might explain my surge problem at idle... Thanks I will give it a try.

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No, this is wrong. There is no egr vs non egr ECU or auto vs Manual ECU. They are all the same computer. There is a pin in the ECU connector that needs a wire going to ground to tell the ECU it is in a manual transmission car. With that wire grounded, the ECU knows that there is no TCU to talk to and no EGR to manage because no M/T cars had EGR. Figure out which pin that is, ground it, and that cures two of your codes.

 

I would use the cooling fan control. It works well and if the engine coolant temp sensor fails, the ECU failsafes to running the fans continuously.

 

Do you have a neutral switch and a clutch switch hooked up? The ECU will want to see those if it's a M/T. WIthout those you get stalling if you coast up to a stoplight and push the clutch in because it's still in decel fuel cut and doesn't get the pedal switch warning that it needs to start idling the engine.

 

It's pin 81.  Should be grounded for MT.  (grounding drives the volts low.  pin voltage chart says MT=0)

 

In this case that may solve the EGR.

 

It's almost impossible to get reid of it on 2.5-2.2 swaps in Outbacks, because all of them AT or MT had EGR.  So if your using a 2.5 ECU it doesn't matter MT/AT.  anyhow.....not really the case here.

 

Also, the newly posted trick of looping the EGR port opening into the IAC hose may solve any EGR issues not resolvable with the ECU end of things.

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Yeah I thought pin-81 also. But after looking at this diagram, that pin (81) receives ignition power during starter cranking through the Inhibitor Switch, if it is in park or neutral.

post-33-0-88381500-1367143678_thumb.jpgpost-33-0-58281500-1367143690_thumb.jpgpost-33-0-09554400-1367143694_thumb.jpgpost-33-0-83400500-1367143699_thumb.jpg

Edited by SkankinPickle

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Yea, there's something goofy going on with the diagrams that have been posted, as they do not match some of what I have (I cannot find the '95 pinout that I've used before, but I have some very reliable diagrams).

 

My diagrams suggest that pin #81 is the starter signal. Which would explain why that screwed up your cold starting. But the diagrams don't list the identification pin.

 

 

Also, the neutral switch is the same wire for AT/MT. So the fact that that wire wasn't there, leads me to believe that the pinout doesn't match your harness.

 

 

 

What color was the wire you found at #81?

Edited by Numbchux

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I don't remember offhand what the color was, I will check in the next day or so and get that info while I undo what I did the other day when I grounded it. One thing to note, about 10" from the ECU the wire (pin 81) was factory crimped to a larger gauge wire with the same color combo. I want to say it was an orange/yellow combo but I'm not 100% on that. I will look tomorrow...

 

Thank you for the help it is very appreciated....

 

Spencer

Edited by obk25xt

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I don't remember offhand what the color was, I will check in the next day or so and get that info while I undo what I did the other day when I grounded it. One thing to note, about 10" from the ECU the wire (pin 81) was factory crimped to a larger gauge wire with the same color combo. I want to say it was an orange/yellow combo but I'm not 100% on that. I will look tomorrow...

 

Thank you for the help it is very appreciated....

 

Spencer

Yep, red with a yellow stripe. Stepped up to a much larger wire. That's definitely the starter signal. Which matches my '95 diagrams.

 

 

I'll do some more digging tonight and see if I can find an actual '95 pinout for you.

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Yep, red with a yellow stripe. Stepped up to a much larger wire. That's definitely the starter signal. Which matches my '95 diagrams.

 

 

I'll do some more digging tonight and see if I can find an actual '95 pinout for you.

 

That'd be great. I should be able to get a lil time under the dash to figure this out on Sat..... 

 

I found some info on SLI that maybe helpful, It shows pin 81 still being the MT/AT identifier (I think), but shows it in a different location. Maybe someone with a lil better understanding can help sort this out.....

 

http://www.sl-i.net/FORUM/viewtopic.php?f=10&t=20667

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The connector diagram on an ECU pinout is looking at the ECU connector.

 

And on the wiring diagram, it's looking at the connector on the harness.

 

 

So they're mirrored from each other.

 

 

 

The wire that goes through the inhibitor switch or starter interlock relay is the starter signal, not the identifier.

 

I looked at a '97 diagram, and that's on pin 86, which matches the pinout posted in the other thread. So that pinout was NOT for a '95.

 

 

 

Edit: I just did some more digging. I don't have a good pinout for a 95, but I did a little copy/paste of that pin from the diagrams from a 97 and 95 Legacy. Pin 81 is correct for a 96-99, but for a 95, you need pin 50.

 

Sorry I didn't catch this sooner!

post-1988-0-95706000-1367077565_thumb.jpg

Edited by Numbchux

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OK.... So I corrected the start circuit, and grounded pin 50. There was NOT a wire for pin 50 in the plug, so I added one. I took pictures of the location if for some reason there should've already been a wire there. 

 

After about 10 min of driving the CEL came on. Also, the engine died When rolling in nuetral on a freeway offramp, I didn't realize it until I was at the stoplight. 

 

Had the codes read, it was the same P1500 for the cooling fan relay, and P0505 IAC malfunction. Those were the ONLY codes thrown, so I am optimistic about the AT/MT issue. Also, I've never gotten the IAC code before.

 

I am thinking, disassemble/clean the IAC, reassemble, and see what happens. I'm pretty confident there are no vacuum leaks etc. 

 

Suggestions?

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For the Fan, Create a main relay and hook the fan up to it.  It might seem like a lot of work, but it is really easy once you get into it.

I just took an extra female 4-prong connector, swapped the wires out of the plastic plug using a sewing needle, and swapped in the correct gauge wires from other parts of the chopped up harness.  I believe you could use the larger wires from an ignition switch connector.   Then just splice the three in to the harness and send one wire to the fan. 

P1500:  Use this to hook up the fan;)

attachicon.gif1995 Cooling System.jpg

The main fan relay is in the fuse box "F/B" inside the car behind the kick panel if the legacy did not have A/C.  

Here is the main-power-routing-diagram that shows how the Main-fan-relay (this would be the secondary fan relay if the car has A/C, and is labeled in diagram on pg. 2) 

attachicon.gif1995 Main Power Distribution pg1.jpgattachicon.gif1995 Main Power Distribution pg2.jpg

This is how you want to set up your relay to control your cooling fan with your ECU.

 

 

P0505:  Trouble shoot pages from '95(I swear) FSM:

post-33-0-45582200-1367146540_thumb.jpg

post-33-0-44216900-1367146547_thumb.jpg

post-33-0-05931200-1367146552_thumb.jpg

post-33-0-66729400-1367146555_thumb.jpg

post-33-0-13097200-1367146560_thumb.jpg

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This is the updated Engine Management diagram showing the color of the wires for the IAC valve.

Yeah I thought pin-81 also. But after looking at this diagram, that pin (81) receives ignition power during starter cranking through the Inhibitor Switch, if it is in park or neutral.

attachicon.gif1995 Engine Management diagram pg1.jpgattachicon.gif1995 Engine Management diagram pg2.jpgattachicon.gif1995 Engine Management diagram pg3.jpgattachicon.gif1995 Engine Management diagram pg4.jpg

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