1jz wiring, ISCV etc

[ms53wagon]

Soo, in the never ending battle to get my 1jz to idle when cold i have narrowed it down to a couple of thoughts from reading through various posts....

1: ISCV does not click open when engine turned off, therefore wont idle when cold...

i got a copy of the ECU pinouts the other day to check over things (as i didnt wire up the car) and im pretty sure the M-REL wasnt wired up....?. the pin-outs were for a 1jz-gte whereas i just have the 1jz-ge, however they seemed to me to be the same?

how do i check the M-Rel is wired up?, also how do i check to see if any error codes, i read that you bridge the E1 and TE1 on the diagnosis block??



Other things i have done:

i have changed the caps in the ECU, so hopefully that little prob is fixed (they were leaking quite alot).

ive also tried a couple other ISCV's - no help

Any input appreciated.

cheers

[wilbo666]

OK, you've prbly found these but if you haven't this is what I'll be referring to!

Wiring Diagram:
http://www.jzgte.com/tech/1jzgte/Soarer.pdf

ECU Pinouts:
http://img322.imageshack.us/img322/3503/jzz309gp.jpg

and

http://www.trackdaymedia.com/~manny/...0__pinouts.pdf



Ok with that sorted, lets have a look at the first document...

Here is another document that tells us how the M-REL system is meant to work!

http://www.autoshop101.com/forms/h25.pdf

At a quick look I'm pretty sure 1jz-gte use "Dual Relays, Ignition Switch or ECU controlled"


Looking at the JZZ30 wiring diagram:
If you want to set your M-REL up so that it runs correctly, you should have...
>A 30A fuse supplying power to common connection on a normally open relay
>The switched power out of the relay goes to the +B and +B1 terminals on the ECU (these are joined inside the ECU as well in case you were interested!)
>The relay is trigger by the M-REL output of the ECU

Hope this helps, let me know if anything doesn't make sense?!

It might be an idea to trace / work out what is going on with all your other wiring and check it has been done correctly

Cheers
Wilbo

[ms53wagon]

legend!!

will have a look this evening and see what i can find.

although my ECU pinouts do not look like the one you posted??

ill find the copy of the ECU that is the same as mine and post later

cheers

[wilbo666]

OK, I thought you mentioned that you had a Soarer 1JZ-GTE in the past... maybe I was wrong?

The pinouts, and wiring diagram that I posted are for JZZ30.

If they don't match what you have it is likely that you have JZX81 or JZA70.

The M-REL output works the same at any rate

JZA70:
http://www.jzgte.com/tech/1jzgte/1JZ...iring.v1.1.pdf

and

http://www.1jz.com/tech/docs/wiring/1jzecu_diagram.gif

Cheers
WIlbo

[ms53wagon]

might not have mentioned but its a 1jz-g and its in an old ms53 crown wagon.

will work on gettin some pics up when i get this sorted!

mad respect dude, cheers

[wilbo666]

Yah, knew it was in a MS53, just got the flavour of 1JZ wrong

Cheers
WIlbo

[1JZ~lux]

Not sure if you have the M-Rel in but wired wrong or if you just don't have one, but if you do have one, the guy that wired it may have connected it to the IGN wire. That's what they did wrong on mine. I also connected the starter solenoid to one of the ECU pins because I was told by a guy that speciallises in engine conversion wiring told me it had a second funtion as a cold start but I can't remember which pin it is (I think it had something to do with auto transmission). Maybe Wilbo knows which pin I'm talking about. I could look it up but I'm in a different state to my Lux for the next 2 months.

[Jabtronic]

Anybody got pinouts for the actual plug on the ISCV?

What should happen when you disconnect the ISCV plug whilst the engine is running? On mine nothing happens, I havn't noticed it click either.

[wilbo666]

Anybody got pinouts for the actual plug on the ISCV?

Below is 7mgte, but might be worth checking if it is the same

I'd suggest the resistance test as a good one to tell if the pinout is the same. This will pretty well only tell you which pins are the common power however...

If you want you can trace the ISCV wires back to the ECU to determine the pinout at the plug!



Cheers
Wilbo

[ms53wagon]

soooo.....

after a couple of hours chasing wires and undoing electrical tape i have found the problem!!!!

i couldnt figure out how he had wired the relay but now it all makes a bit more sense.

here is what i found, i believe the ignition is wired to activate the EFI relay (and fuel pump relay), 12v from the battery powers through the relay once activated to provide power to all of the following:

BT, BATT, +B, and IGSW... i dont know why they did it like this? i mean the car seems to run fine apart from the idle issues. although i was wondering if this has any other non critical implications??, when following the wiring diagram the +B seemed to provide power to oxygen sensor??

anyway, its too late now to re-wire but atleast i know what im up against tommorow evening.

will keep updated

cheers

[ms53wagon]

Jabtronic: i have been driving round with ISCV disconnected for a day or two now, i dont know if this is a problem but it seems fine?

when it was connected it will close too much to even idle when warm, so i backed it off a little (by ground S4-S3-S2-S1 repeatedly as per Wilbo's diagrams) then disconnected it.

this way it lets a small amount of air past TB to keep idle slightly up....i know this is a pretty rude way to do it but it works till i get the wiring sorted properly.....then possible a tune?

cheers

[Jabtronic]

Yeah mine does nothing whatsoever when I unplug the ISCV (engine cold or warm), so something must be wrong there. I know that the middle two pinouts have 12v though.

Cheers Wilbo, I'll test it out now.

[1JZ~lux]

It seams to be a common fault for the M-Rel to be wired wrong. The pro that helped me said that Nissans use similar colours but to do different things to a Toyota so people mix them up heaps if they're not using diagrams.

[Jabtronic]

Below is 7mgte, but might be worth checking if it is the same

I'd suggest the resistance test as a good one to tell if the pinout is the same. This will pretty well only tell you which pins are the common power however...

If you want you can trace the ISCV wires back to the ECU to determine the pinout at the plug!

Cheers
Wilbo

I tested resistance, each way was 47ohms (should be between 10-30?) Then I tested that the ISCV opens and closes using the method, which it does.

Then I tried testing continuity of each of the 4 'S' wires on the plug back to the ECU. Nothing... Is there something in the middle?
According to the diagram I have, and http://www.1jz.com/tech/docs/wiring/1jzecu_diagram.gif
S1/ISC1 = White-yellow
S2/ISC2 = Green-white
S3/ISC3 = Blue-red
S4/ISC4 = Red-black
None of the 4 wires could be traced to the ECU, so I'm going to have to pull the loom out and manually follow them.

[wilbo666]

soooo.....

...

here is what i found, i believe the ignition is wired to activate the EFI relay (and fuel pump relay), 12v from the battery powers through the relay once activated to provide power to all of the following:

BT, BATT, +B, and IGSW... i dont know why they did it like this? i mean the car seems to run fine apart from the idle issues. although i was wondering if this has any other non critical implications??, when following the wiring diagram the +B seemed to provide power to oxygen sensor??

Yep, that sounds all manner of wrong!

Lets break it down...

BATT: This should have constant battery power...run a new wire with a fuse directly from the battery. If BATT isn't connected in the manner I described, then your ECU will have to relearn its fuel trims, idle, etc every time you turn it on (dumb).

+B, +B1: These should be the output form the M-REL as prev discussed

IGSW: This should get fed power (+12V) from the ignition barrel when the ignition key is in the crank and run position, this is what the ECU uses to know when to trigger the M-REL on/off.

And we have already talked about how to power the M-REL and that it is triggered by the M-REL pin on the ECU.

You also should set your fuel pump to be triggered by a Circuit Opening Relay, do a search and you should get heaps of info on how to do that. If you have any dramas let us know

Hope this helps

Cheers
Wilbo