US over to europan.

[Trevor]

Originally Posted by oab_au

OK, I think you are placing a lot of your thinking around this statement, “Alex has stated that when he inserts the fuse, front wheel drive only is engaged. Therefore the signal now is correct for the system.”

This is right, but only when the fuse is inserted. This is the only time that the two TCU send the same signal for the same action. When the US fuse is inserted for FWD, the TCU sends a 95% signal to turn off the clutch. When the VTD fuse is in for DIFF LOCK, it sends a 95% signal, to turn on the clutch

The US trans has the clutch turned off, and the VTD has the clutch turned on. Its because the C solenoids are opposite to each other, that the US solenoid turns off the clutch. The VTD solenoid turns the clutch full on.

With Alex’s car, when the VTD TCU detects wheel spin, it will send a 95% signal to apply the clutch, but the US solenoid, being opposite, turns it into clutch off.
When he is turning tight, the VTD TCU sends a 5% signal to turn the clutch off, the US solenoid turns the clutch on, to cause the binding.

Changing the US solenoid for a VTD solenoid, will turn these signals back the right way, binding will not occur, and wheel spin will be prevented.

Harvey.

Harvey,

As usual you twist what is fact and what is true, in an attempt to prove a theory, which is wrong. Forget the percentage jargon. Confine actions to the binary. All else follows.

Inserting the fuse results in exactly the same control signal, in respect of the orientation of the pulses, as when normal control is functioning. The difference you describe is not in fact required. This is a figment of your imagination, alight as a means of justifying another fairy story.

The signals do not require turning back the right way. They are the right way. The signals are the same for both TCU. It is the final action which takes place, as a result of the signal, which is different in the two systems. The same signal achieves the same result due to the use of a different orientation of valve in each system.

!. A lengthening pulse energises the solenoid and extends the armature. 2. A shortening pulse allows the armature to retract.

1. Closes a N/O. valve. Opens a N/C valve.
2. Opens a N/O valve. Closes a N/C valve.

It is the relationship between the non electrical controls which requires “reversal” , and the difference in solenoid valve configuration achieves the required result. N.B. This relationship will mean a second “reversal” and therefore, no reversal, in the event that your theory is applied.

Normal VTD system. --- When increased front bias is required, (Or the fuse switch fitted to provide a locked up drive.) the pulse length will be increased, (Or a constant signal transmitted.) in order to close a N/O solenoid, thus increasing pressure, to close a LSD clutch. The TCU will be programmed to increase the pulse length.

With Alex' car. --- When increased front bias is required, (as when inserting the fuse switch), the same increased pulse length command, (or a constant signal) will open a N/C solenoid, thus reducing pressure, to open the centre clutch. The TCU will be programmed to increase the pulse length.

Think about it.

[Trevor]

All those reading this thread, should consider the problem which is overcome within the original equipment, along these lines. ----

Consider the very first application of a relay, i.e. a telegraph circuit.

A morse key energises and de-energies a telegraph line. At the far. end a relay follows the signal.

A normally open contact fitted to the relay, will provide a “positive” signal comprised of dots and dashes, i.e. the original signal.

A normally closed contact will provide the same signal in a “negative” form.

Normal signal, on = on. Modified signal, on = off.

The latter does not constitute a true “reversal” of the signal, but is what is required in the respect of the application being argued. It should be noted that for good reason, I have of late, referred to the changed result using quotation marks.

P.S. "Inverted" would probably be a better description.

[TomsSVX]

/me facedesks....

Tom

[Trevor]

Originally Posted by TomsSVX

/me facedesks....

Tom

Thank you Tom.

You confirm that I have been correct in two ways. You are indeed an intelligent, gentleman of honour.

Having moved from sitting at the top of the class, so as to have a good overall view of things, please throw something nasty at that student way down under at the bottom of the class.

Sincerely, Trevor.

[Trevor]

Harvey,

Apparently intestinal fortitude is lacking. A reply is expected, as it is recorded that, you have thrice, had the time to view your now adopted forum.

Patiently waiting. Trevor.

[Marcus]

Originally Posted by Trevor

Harvey,

Apparently intestinal fortitude is lacking. A reply is expected, as it is recorded that, you have thrice, had the time to view your now adopted forum.


Patiently waiting. Trevor.

Dear Trevor,

please take the effort and read the thread again and reconsider about your real aim.
You will come to notice that Harvey came up with a recomendation for a solution to the problem described by the originator of the thread.

Harvey argued that the US-Type Solenoid C operates the wrong way to be used for the European-Type Tranny.

Maybe your recomendation got lost between the many lines you wrote (or in other words: the many insults twards Harvey might distract from the real message), but I cannot find it.

To be very honest: Subtracting insults and teacherous babble, I cannot find anything worth to notice, which was not said before.

To refocus: From the little be left after subtracting I realize you also believe a switch of Solenoid-Type will do the job. I like to agree! (Alex, good luck with repairing your SVX!)

Trevor, I believe we all would be better off, if you could let go from your hassle with Harvey and would start to focus on helping comrades with their technical questions again. But if I remember correctly: I am not the 1st one to mention that to you, am I?

Kind Regards

Marcus

[Trevor]

Marcus,

I take exception to your remarks. My facts are proven. Please read through the thread a second time and comprehend.

[b3lha]

I'm now a little reluctant to post in this thread because I don't want to get caught up in this relentless bickering about solenoids and duty cycles. I am only posting this because I think it might be helpful and I want to get it in before the thread gets locked.

Here are a couple of diagrams that might be useful to Alex, or anyone else considering fitting a US transmission and TCU to a European or Aussie car.

This first diagram is the JDM/USA wiring. You can see speed sensor #2 mounted in the front diff has three wires. Pin 1 is signal, Pin 2 is ground, Pin 3 is power (not sure 12v or 5v ???). The Signal wire connects through to pin a11 of the TCU, it also feeds the ECU, speedometer and cruise control unit, but that is not shown on this diagram.

http://www.subaru-svx.net/photos/files/b3lha/33820.jpg

The second diagram is the Euro wiring. You can see the speed sensor #2, mounted internally to the gearbox, has a ground and a signal wire. No Power wire. The signal wire connects through to pin a17 of the TCU. But look up a bit and you can see a wire coming out of pin c6 that feeds back into pin a11 and also runs to the ECU, speedometer and cruise control.

http://www.subaru-svx.net/photos/files/oab_au/13771.jpg

I am 99% sure that the TCU has a circuit that converts the Euro-type signal to a US-type signal. The input is a17 and the output is c6.

I suggest that in order to fit a US TCU, you need to connect the VSS2 signal and ground wires to the sensor in the front diff, and add a third wire suppling power.

Then at the TCU end, you need to snip the wires going into a17 and out of c6 and join the loom side of them together. because you don't need to route the signal through the conversion circuit.

I can't say for sure if this is what Barry did to his car, but I reckon it's a good start.

The other change that will probably be necessary is to simulate an atmospheric pressure input to the US TCU. I would try Ron's (untested) 4-stage power mode mod for US TCUs. The voltage level on the atmospheric pressure pin determines whether the TCU uses Normal, LowPres1, LowPres2, or Power shift modes. See the gearshift maps thread for diagrams. I would use a potentiometer, start off at 0 volts and increase very slowly until the error code goes away. Then if you want a slightly sportier shift, increase a little more until it changes up a mode. I wouldn't go above 5 volts for fear of cooking the TCU. Once you discover where the voltage thresholds are, replace the potentiometer with a 4 position rotary switch and a resistor ladder.

I hope that helps.

[Alex-svx]

I have look on the diagram and i see that is say, Speed sensor out of the gearbox. So when i change the TCU, then i have to coneck the speedsenor from the front diff. to the wiring system.

Because if i have had a US verson car, Then the TCU wiring has been coreck for the Speed sensor that is on the front diff? That is way i have to ''convert'' this from the wiring system that i have now are this rigth?

So if you in the US chage the gearbox then you use the speedsensor on the front diff. And then i belive the speed cluster has to be change to, for then i lose the KM/H and must have MP/H are this also rigth? I have US speed cluster at my home also, But i have try this on the car and my car will not read this corekt.

(Pleas corekt me if i am wrong)

[svxistentialist]

Originally Posted by Alex-svx

I have look on the diagram and i see that is say, Speed sensor out of the gearbox. So when i change the TCU, then i have to coneck the speedsenor from the front diff. to the wiring system.

Because if i have had a US verson car, Then the TCU wiring has been coreck for the Speed sensor that is on the front diff? That is way i have to ''convert'' this from the wiring system that i have now are this rigth?

So if you in the US chage the gearbox then you use the speedsensor on the front diff. And then i belive the speed cluster has to be change to, for then i lose the KM/H and must have MP/H are this also rigth? I have US speed cluster at my home also, But i have try this on the car and my car will not read this corekt.

(Pleas corekt me if i am wrong)

Alex I suggest you get an auto electrician to read carefully the last paragraph in Phil's post above, #68, and follow these instructions carefully. I am presuming also that you still have a Hall Effect sensor for SS2 installed in the front diff housing. If this is not the case please tell us.

The speed cluster from your own car should work. It gets its signal forwarded from the TCU, and I think [but don't know for certain!] that your original box probably had the same Hall Effect sensor on the diff. Can you remember?

The sensor merely measures the number of times the axles turn, and this information is sent to the speedo as a signal. It should make no difference to the speedo hand whether it is passing a kilometres figure or a miles figure on its way round the dial; the speed is displayed by how far around the dial the hand is sent.

Joe

[TomsSVX]

Originally Posted by svxistentialist

Alex I suggest you get an auto electrician to read carefully the last paragraph in Phil's post above, #68, and follow these instructions carefully. I am presuming also that you still have a Hall Effect sensor for SS2 installed in the front diff housing. If this is not the case please tell us.

The speed cluster from your own car should work. It gets its signal forwarded from the TCU, and I think [but don't know for certain!] that your original box probably had the same Hall Effect sensor on the diff. Can you remember?

The sensor merely measures the number of times the axles turn, and this information is sent to the speedo as a signal. It should make no difference to the speedo hand whether it is passing a kilometres figure or a miles figure on its way round the dial; the speed is displayed by how far around the dial the hand is sent.

Joe

Wait, Euro models relay the speed sensor signal to the dash?? That is not how the US system works

TOm

[b3lha]

Originally Posted by TomsSVX

Wait, Euro models relay the speed sensor signal to the dash?? That is not how the US system works

TOm

Refer to the diagrams in my previous post.

On the US model, the VSS2 signal goes directly to TCU pin a11 and the ECU and dash.

On the Euro model, the VSS2 signal goes to TCU pin a17, gets modifed into a US-style signal, then comes out on pin c6. This modified signal is then fed back into TCU pin a11 and the ECU and dash just like on the US model.

[svxistentialist]

Originally Posted by TomsSVX

Wait, Euro models relay the speed sensor signal to the dash?? That is not how the US system works

TOm

I could be wrong Tom. My wiring manual is in the UK.

If you look at this diagram Plug B14 you will see there is an output coming from the TCU, two yellow and black wires, and they are connected to the ECU with a feed off to the speedo.

Maybe Phil would have a better idea of the difference, he has in the past altered his speedo reading from kms to miles, so he may understand the diferences in wiring.

Joe

[Alex-svx]

Originally Posted by svxistentialist

Alex I suggest you get an auto electrician to read carefully the last paragraph in Phil's post above, #68, and follow these instructions carefully. I am presuming also that you still have a Hall Effect sensor for SS2 installed in the front diff housing. If this is not the case please tell us.

The speed cluster from your own car should work. It gets its signal forwarded from the TCU, and I think [but don't know for certain!] that your original box probably had the same Hall Effect sensor on the diff. Can you remember?

The sensor merely measures the number of times the axles turn, and this information is sent to the speedo as a signal. It should make no difference to the speedo hand whether it is passing a kilometres figure or a miles figure on its way round the dial; the speed is displayed by how far around the dial the hand is sent.

Joe

My (stock tranny) has not have a sensor in the diff. But on the new one i have a sensor in the diff but the wiring is cut of. (i have not cut the wiring)

Ok so i understand this rigth then this have no effeck on the Speed cluster on the car? If i must use MP/H or KM/H has that mean nothing to me. I can drive whit MPH also. I think i have heard this before about the sensor in the diff but iam not 100%sure.

[TomsSVX]

Originally Posted by b3lha

Refer to the diagrams in my previous post.

On the US model, the VSS2 signal goes directly to TCU pin a11 and the ECU and dash.

On the Euro model, the VSS2 signal goes to TCU pin a17, gets modifed into a US-style signal, then comes out on pin c6. This modified signal is then fed back into TCU pin a11 and the ECU and dash just like on the US model.

Thats what I wanted to hear, thanks for clearing that up.

My bet is going to be he has a 2 wire VSS2 in the trans now because that is what the Legacy used, he is going to need an SVX style sensor

Tom