52 replies to this topic

[Prwa101]

ECU still isn't grounding though...

Should I open up the Ecu and check it out?

Edited by Prwa101, 16 July 2012 - 06:32 PM.

[Prwa101]

Still havnt figured it out.... Ecu still isn't growing the fuel pump relay... I opend it up looks clean and I can't see how it'd be bad since I drove the car home, and the Ecu and harness has need sitting in my room on a shelf for a couple months.... Hmmm

What grounds, ground that green fuel pump relay Ecu wire?

Or how do you tell if the ecu is on? If I'm missing a power...

[eulogious]

Double and triple check all your grounds. You need to have multiple grounds for this thing to work for ya, I am guessing you are missing one or more of them...

[GeneralDisorder]

Do you have any wires from the ECU that do not end at a device connector, ring terminal, or are not labeled as to their exact function?

Grounds and power supplies should end up being pretty obvious in the harness stripping process as they are wires that have to be cut or that end in ring terminals. Some of the ECU grounds are on the intake manifold and pass through the manifold harness connection - some years have only these grounds and no others - other years have additional grounds that you have to bolt to something yourself.

GD

[Prwa101]

It's a 93 leg ej22 harness and ecu, the diagrams I have don't seem to fully match up( can't find the 93's). Could this be where I have an issue? The 93 maybe had another site or something that needed to be hooked up??? Anyone know?

[Crazyeights]

Like several have said it sounds like a grounding issue. I just got done with my '93 harness and swap a few months ago so it's still fairly fresh. I would start with an ECU pin-out chart. Locate EVERY ground going to the ECU and triple check that you haven't missed one, there are multiple grounds. I actually trimmed a few of the needed ones out (easy to do) and caught them with this check. I also missed one 12v small yellow wire power connection to the diode in the harness. This caused a no-start (no power to fuel pump). With these sorted my swap has been running perfectly for months now. Sounds like you're close - stay with it!

[Prwa101]

Okay did some checking on the grounds, F47 (D) pin 14 and 15 are grounds, power supply and igniting, bot of thouse are getting .57 and .66v in the on position! Sound bad?

And can I splice into thouse news the ecu and ground them locally? (if .5v is bad of course)

[Prwa101]

Ya ground issue... I groused that pin 14 got .3v at the FP wire. Grounded more and got .5v. Time for grounding!!

Thanks guys!!!

Edit:

IM GOING CRAZY.....

Edited by Prwa101, 23 July 2012 - 08:10 PM.

[GeneralDisorder]

Pardon me if I'm completely blunt about this and don't take it personally cause you are learning and that's ok.....

You haven't got the first clue how to run a meter and check what needs checking. Either that or I'm not grasping how you are describing what you are testing.

This:

"F47 (D) pin 14 and 15 are grounds, power supply and igniting,"

Is not making any sense. A pin is either a ground source for the ECU or it's a power supply to the ECU.... or it has another function. They can't be both.

These voltages you are reading are meaningless "ghost" voltage. Numbers like .5 and .6 volts are effectively zero for the purposes of troubleshooting and a reading going up 0.1v when you ground a pin on the ECU is effectively no change at all. That's not in the granularity of what you are looking for. You should be looking for 12v at the pins supplying power and you should be looking for 0 (Zero) Ohms of resistance when probing a ground pin - both tests are done with the ECU hooked up and probing from the back side of the connection.

You need some guideance here but I'm not totally sure how to help you. I don't have the time to get out there myself and I'm sure you probably don't want to tow the thing down to my shop so..... the only thing I can think is to have you hang out at the shop when I'm troubleshooting something of this nature.

GD

[Prwa101]

Pardon me if I'm completely blunt about this and don't take it personally cause you are learning and that's ok.....

You haven't got the first clue how to run a meter and check what needs checking. Either that or I'm not grasping how you are describing what you are testing.

This:

"F47 (D) pin 14 and 15 are grounds, power supply and igniting,"

Is not making any sense. A pin is either a ground source for the ECU or it's a power supply to the ECU.... or it has another function. They can't be both.

These voltages you are reading are meaningless "ghost" voltage. Numbers like .5 and .6 volts are effectively zero for the purposes of troubleshooting and a reading going up 0.1v when you ground a pin on the ECU is effectively no change at all. That's not in the granularity of what you are looking for. You should be looking for 12v at the pins supplying power and you should be looking for 0 (Zero) Ohms of resistance when probing a ground pin - both tests are done with the ECU hooked up and probing from the back side of the connection.

You need some guideance here but I'm not totally sure how to help you. I don't have the time to get out there myself and I'm sure you probably don't want to tow the thing down to my shop so..... the only thing I can think is to have you hang out at the shop when I'm troubleshooting something of this nature.

GD

No man it's fine! Be blunt as you want! Yeah learning a lot...

For pin 14 and 15, it the ecu pin out, it says grounds (ignition) and grounds (power supply) but I know what you mean there! Haha. I'm not that new to wiring haha.

Ahhhh "goast" makes Sence why it went away..,, haha. And I thought I was going crazy!

12v for power

0 ohms for grounds! Did not know this!! Good to know!! Haha.

I completely understand! And I want you to know I apprishiate all the help you have given me!!

BUT HUGE UPDATE:::::::

I desided to pull the harness out of the car and run through the diagrams more till I find something! So I got it out started looking through it and POW! Or more like bzzz 'melt'



It looks to me that before I had fixed the ignition relay wire (or something) can't remember it shorted it out and melted it... It melted the diode! Now could this cause the issue? I kinda think yes. Haha.

AND!!

(not connected to the diode) but near it I have a dark yellow wire Named "fuse box needs power" that goes to the "ignition coil" "ALT-2" wich is the fuel box?, and then goes to the diode?? Should this get switched power or always have power??

Now correct me if I'm wrong, I had it set up having power go through the wires coming from the ignition relay, sending out power from the ignition relay. (don't as me how) haha. But I'm guessing it only likes power going one way through the diode? And when I had pushed it through the opposite way it toasted it? And I found out it goes to D5 12v in the "on" and running.

Now let's fix this issue and look through the diagrams and see what else I come up with!!

Thanks GD!

Edited by Prwa101, 25 July 2012 - 07:46 PM.

[GeneralDisorder]

Fried diode is bad. Get a replacement from the junk yard and solder it in place.

The yellow wire that goes to the alt and coil, etc should be connected to switched +12v. The OBD-I alternators won't charge without this +12v input to the regulator in the alt.

GD

[Prwa101]

Yup! And the sucky thing is... I was just there today getting some studs.... Gah.. Haha. It's cool I got more things I need to get anyways.

Oh and found something interesting


"A diode allows electricity to flow in one direction only and blocks the flow in the opposite direction"

Makes a lot of Sence why It wasn't working! Going to get that tomarrow!!

Thanks GD!! Glad I didn't give up.. I was close....

[GeneralDisorder]

Grab a couple in case your wiring still has whatever problem fried the first one.

GD

[Ioku]

Maybe this will help, its how the fuel pump is wired stock in an ea82, assuming thats what your swaping into. And hear is were I think your problem is, in the ea82 system the ground for the fuel pump its self is done though the ecu but this is not the case with the EJ ecu, in the ej system the fuel pump is just grounded to the body. So try grounding the black wire at the fuel pump and see if that works. Also be sure your using the control wire comeing off the EJ ecu to ground the control side of the fuel pump relay. And for powering the control on the really use a hot at all times power source and not the power out of the ignition relay use that on the switched side to send power to the pump.

I also suggest you put away the volt meter and get your self a test light its a lot better for work like this were all you care about is 12v power and ground, and will help to keep you getting confused with meaningless 2 and 3 and half volt readings.

[ivans imports]

just use the green and black wire to turn on the factory feul pump realy and do not need legacy one just swap out the signal wires

[ivans imports]

if you look in your left over harness parts you may find the same diodes they use them in ac or use the other curcut in your damaged one is the same

[Subruise]

Maybe this will help, its how the fuel pump is wired stock in an ea82, assuming thats what your swaping into. And hear is were I think your problem is, in the ea82 system the ground for the fuel pump its self is done though the ecu but this is not the case with the EJ ecu, in the ej system the fuel pump is just grounded to the body. So try grounding the black wire at the fuel pump and see if that works. Also be sure your using the control wire comeing off the EJ ecu to ground the control side of the fuel pump relay. And for powering the control on the really use a hot at all times power source and not the power out of the ignition relay use that on the switched side to send power to the pump.

I also suggest you put away the volt meter and get your self a test light its a lot better for work like this were all you care about is 12v power and ground, and will help to keep you getting confused with meaningless 2 and 3 and half volt readings.

i suggested this (albeit without diagram) very early in this thread

[Prwa101]

Not to be rude. But it's not the ea side. I can stick any 12v on the ea fuel pump wire and get it to go. The ej ecu isn't grounding the ej fuel pump relay like it should.

Got the new diode in. And still nothing... I'm debating on getting a new harness... Or cutting this one up and fallowing http://www.shoptalkf...p?f=19&t=136053.
As a start over..

I've double checked ever ground and power... And don't see anything wrong... I have the harness out now, been looking trough it for a couple hours now...

Dang I even got my 29" tires on the rear now... Haha. So close..

Maybe I'm missing a wire to hook up some where for the first fire off.... What all needs to be wired and tapped into for it to run? I know the main power, starter wire, ignition switch 12v on. I think that's all I've had so far...

Edited by Prwa101, 29 July 2012 - 10:35 PM.

[Ioku]

Do you have all the ecu grounds wired up.

[Prwa101]

Do you have all the ecu grounds wired up.

All of my ecu ground head toward the intake where there are two grounded points. I don't see where I could have messed up..... Gosh I love wires... Had dreams about It last nigHt haha.

[Prwa101]

I stubled across this today, http://forums.nasioc...d.php?t=1077542

Numbchux had the same problem, said it was grounds/power... Going through the harness agin... Haha. gosh I want this car running!

[Gloyale]

All the ECU grounds happen at the engine harness.

You need to have the intake harness plugged into the main harness, and the ground eyelet grounded to the intake.

Without that, the ECU won't have ground sources.

[Prwa101]

All the ECU grounds happen at the engine harness.

You need to have the intake harness plugged into the main harness, and the ground eyelet grounded to the intake.

Without that, the ECU won't have ground sources.

I checked thouse Eyelet yesterday it looked good and clean. I have it plugged in too haha.

Does the newtral switch, parking switch or any of thouse have to be hooked up?

I ruled out the battery being the problem today...

[Gloyale]

will it run the pump with the test connectors plugged?

Do you have 12v start signal wire of ECU connected to the starter circuit?

[Prwa101]

Well... Good news is that I'm retarded... Better news is I'm working on fixing my retardedness.... I was so fixated on the harness, I wasn't paying any attention to the battery... I got the posts backwards... In my old loyale it had a bimart battery that was turned around so the cables had to reach farther... I thought this bimart Battry was the same... It wasn't.. Good thing it only fried a fuse able link and nothing else....

Or I fried the ECU......

I got the diode fixed and can get power through it where it needs to go. I thought if check for spark, and nothing...

So no spark and the ECU still isn't controlling the fuel pump relay...

Anyone have any ideas? Should I start over with a new harness and ECU?

On a better note! I got all the interior wiring working and can role up the drivers side window (stupid electril) that's been down since I got it! Dang it's almost been a year that I've been building this....

Thanks guys! Been really busy with work and re doing my parents roof in there house....

-Prwa