jdm svx trans, will it work?

[TomsSVX]

Originally Posted by Trevor

Exactly which solenoid do you now have you fitted? JDM normally open, or US normally closed?

It is the different solenoid which reverses the “command” of the TCU signal. When using a JDM transmission, you must fit the appropriate C solenoid valve, i.e. one that is normally open and NOT the US one which is normally closed.

You should also be using the JDM TCU, otherwise as I have pointed out, the programming will/may not be correct, which is no doubt the current situation. The US TCU is programmed for a clutch, the JDM for a differential.

It was this post. But reading it again, I did misread it. Sorry for the trouble, guess thats why I was baffled

Tom

[b3lha]

You need the JDM TCU to properly control the JDM trans. It should plug straight into the USDM loom. The wiring is the same except that the JDM cars have an extra wire for the power mode switch.

The USDM TCU will not control this box properly even if you do swap in a US-type solenoid. There are substantial software differences between a JDM and USDM TCU.

If you cannot get hold of a JDM TCU, it is possible to reprogram a USDM TCU with the JDM software. I'm pretty sure the circuit board is the same. Try sending a PM to Longassname. He might be able to make one for you.

[svxistentialist]

Originally Posted by b3lha

You need the JDM TCU to properly control the JDM trans. It should plug straight into the USDM loom. The wiring is the same except that the JDM cars have an extra wire for the power mode switch.

The USDM TCU will not control this box properly even if you do swap in a US-type solenoid. There are substantial software differences between a JDM and USDM TCU.

If you cannot get hold of a JDM TCU, it is possible to reprogram a USDM TCU with the JDM software. I'm pretty sure the circuit board is the same. Try sending a PM to Longassname. He might be able to make one for you.

So Phil,

Are you like the fourth , or fifth, or maybe sixth person to say use a JDM TCU to control a JDM transmission, or would you rather enter into the non-debate about how the C solenoid works??

[svxistentialist]

Originally Posted by Trevor

The TCU and solenoid must match the transmission. i.e. US-US-US, or JDM-JDM-JDM, are the only arrangements which will work correctly.

Correct - correct - correct.

[Trevor]

Originally Posted by svxistentialist

Correct - correct - correct.

Therefore no debate exists regarding the existence of two types of solenoid.

The arrangement facilitates the use of similar circuit boards as pointed out by Phil. This fact constitutes further confirmation of my statements covering the overall application.

Incidentally, I have advised regarding a JDM TCU which is available from NZ.

[svxistentialist]

Originally Posted by Trevor

The arrangement facilitates the use of similar circuit boards as pointed out by Phil. This fact constitutes further confirmation of my statements covering the overall application.

Incidentally, I have advised regarding a JDM TCU which is available from NZ.

Yes, that's an interesting observation.

Nice one Trevor. Better to match like with like.

Incidentally I have never managed to figure out why the JDM gearbox, which is VTD as we know, has the same front diff mounted speed sensor as the US gearbox, which is ACT4.

In contrast both of the Down Under VTD boxes and the UK boxes each has the two speed sensors inside the box, so the loom is consequently different. All these VTD markets use the same 3.70 final drive, and the USA uses 3.52 I think. What's difficult to understand is why the RHD Japanese market got the separate front diff speed drive,rather than the internal drive like the rest of the world.

Any ideas?

Joe

[Alex-svx]

Hello.

I just read this thread and i have also chage the tranny to a 4.44.
And the old tranny is trash away, should not happen but anny way.

And i have problem whit the diff lock when i not have the fuse in.
But is it only to reprogram the USDM TCU with the JDM software?? So will the rest work?

[svxistentialist]

Alexander

I'm not exactly understanding what you are describing. Could you give more detail please?

For a start, is the Legacy 4.44 transmission of the same type as the SVX one you removed? Legacy models used both types of transmission, the VTD type same as the SVX, and the ACT4 type, which is the same as the USA gearbox used in the SVX.

Some European markets got the same gearbox as they got in the USA, Germany and France did as far as I know. We have a list somewhere translated from Japanese by Ryu I think.

So I suppose the question is, have you replaced the gearbox in your car with exactly the same type gearbox?

Otherwise you will have a compatibility issue with the Transmission Control Unit.

Please confirm

Joe

[huck369]

Originally Posted by Alex-svx

Hello.

I just read this thread and i have also chage the tranny to a 4.44.
And the old tranny is trash away, should not happen but anny way.

And i have problem whit the diff lock when i not have the fuse in.
But is it only to reprogram the USDM TCU with the JDM software?? So will the rest work?

Did you also change the rear diff?

[Alex-svx]

Yes i change also the rear-diff. But the transmission i have now is from a US model, And the stock is a European verson. My problem is the old tranny got trash away the day after i tok the car out for a test drive. And then i find out the front diff lock when i tur the car. And when i insert the fuse in Diff Lock then the rear diff is not in use and the car could spinn on the front weal. (the car is not in use now).

I have try to find the old tranny but whit no luck, I have just ``rent`` the place there the car was stay on when repair. And the folks that have the place have trash all away the day after i have test the car. And then i find out i also need the C-solenoid

[TomsSVX]

A USDM TCU will fix the issue and be a lot easier to install. This would be suggestion

Tom

Originally Posted by Alex-svx

Yes i change also the rear-diff. But the transmission i have now is from a US model, And the stock is a European verson. My problem is the old tranny got trash away the day after i tok the car out for a test drive. And then i find out the front diff lock when i tur the car. And when i insert the fuse in Diff Lock then the rear diff is not in use and the car could spinn on the front weal. (the car is not in use now).

I have try to find the old tranny but whit no luck, I have just ``rent`` the place there the car was stay on when repair. And the folks that have the place have trash all away the day after i have test the car. And then i find out i also need the C-solenoid

[Alex-svx]

Ok thanks for the help. And this i must have from a US model of a Svx right? Were is this placed on the car? I dont have much experience whit this.

Originally Posted by TomsSVX

A USDM TCU will fix the issue and be a lot easier to install. This would be suggestion

Tom

[TomsSVX]

Originally Posted by Alex-svx

Ok thanks for the help. And this i must have from a US model of a Svx right? Were is this placed on the car? I dont have much experience whit this.

I am not sure what model you have RHD or LHD but if it is LHD it is located under the dash board by the ECU. It is a gold box with 3 black connectors going into it

edit: Why in the world would you switch from a VTD box to a US style?? They are inferior in performance and essentially a step down regardless of the gear ratio.

Tom

[Alex-svx]

Ok, Thanks alot for the help. Then i just to find this box for sale now.
I save a lot to bye this tranny form Us and it was easy to find. And like i said i dont know to much when is about tranny.. But still learning.

Edit. If i dont find one used. Can i bye one of these? www.ecutune.com

Originally Posted by TomsSVX

I am not sure what model you have RHD or LHD but if it is LHD it is located under the dash board by the ECU. It is a gold box with 3 black connectors going into it

edit: Why in the world would you switch from a VTD box to a US style?? They are inferior in performance and essentially a step down regardless of the gear ratio.

Tom

[TomsSVX]

Originally Posted by Alex-svx

Ok, Thanks alot for the help. Then i just to find this box for sale now.
I save a lot to bye this tranny form Us and it was easy to find. And like i said i dont know to much when is about tranny.. But still learning.

Edit. If i dont find one used. Can i bye one of these? www.ecutune.com

As long as the VTD extension was not the issue with the old trans, maybe someone should have told you to KEEP the VTD w/ the US style trans. It as simple as taking the extension housing and sun gears and transfering them. Too late now but that sucks... You can buy whatever trans you want but honestly, I would have had the VTD box rebuilt

Tom