changing shift solonoid outputs

[killalux]

Hey all,
This may be a bit off an odd question but hoping someone can help. I will also add that i do not have tuning software so if someone thinks this is possible i will be looking at sending it thier way.

What i would like to do is to control a toyota landcruiser auto transmission from the ls1 PCM. This is used in a conversion and we are having some issues getting the auto to shift properly with the toyota PCM.

Basically the 2 boxes use 2 shift solonoids primarily to shift gears, plus the TCC solonoid. In this case the holden PCM outputs for the TCC duty cycle, line pressure and 3-2 downshift solonoid will not be used.
The issue is that the way that the 2 solonoids switch is different between the 2 boxes. Can't remember all the details (they are at work) But basically the issue is say for 1st gear in the holden box both shift solonoids are on, whilst in the toyota box one is on and the other is off.
What i want to know is it possible to reconfigure when each output switches so that it will operate the toyota box.

Thanks
Steve

[joecar]

Hi Steve,

Which Toyota transmission are you using...?

Can you post a chart of the gear range solenoid states and some wiring diagrams showing how the Toyota's solenoids are connected to the Toyota controller.

Cheers
Joe

[killalux]

Hey, not sure how to get a chart on here so will list the solonoid states.

1st- S1 on S2 off
2nd- S1 on S2 on
3rd- S1 off S2 on
4th S1 off S2 off

They are wired as positive switching unfortunately, but should be able to use relays the change that so it will work with the GM neg switching. I guess i may also need to add some resistance to the circuit aswell to stop the GM PCM throwing a fault code.

Steve

[joecar]

Toyo (trans):

1st- S1 on S2 off
2nd- S1 on S2 on
3rd- S1 off S2 on
4th S1 off S2 off

4L60E (PCM):
1st-A on B on
2nd-A off B on
3rd-A off B off
4th-A on B off

So it seems to me that you would wire up as follows:
S1 = B
S2 = not(A)

To implement "not" (inverting signal A) you would wire a relay using the normally closed contacts (i.e. "on") and the signal opens it ("off").

Yes, GM uses ground side switching.

[killalux]

thanks very much joecar, didn't think of it like that, will work perfect, now just have to sort out the speed sensor part.
Do you happen to know how many pulses per revoloution of the output shaft the GM sensor puts out.

Thanks
Steve

[joecar]

Steve,

I believe it is 40 pulses/rev.

Cheers
Joe
:)

[joecar]

Hi Steve,

Don't drive the Toyo's positive side solenoids from the LS1 PCM...
i.e. for S1=B you should also use a relay (in the non-inverting manner, using the normally open contacts).

Also...
Are you also controlling the motor...?
If so, have you considered that the CKP reluctor is not "straight" but is "encoded"...?
If not, then how're you tricking the PCM into believing there's a motor on the other end of the wire harness...?

[killalux]

Hey mate,

Yes i will be using the LS1 PCM to drive relay's which will then positive switch the toyo solonoids.

And yes This vehicle has had an LS1 fitted to it and used the toyo gearbox, so at current it has the GM PCM running the motor and the Toyo PCM running the gearbox, But the toyo keeps going into limp mode because it is not getting correct engine speed info, this is why i want to get rid of the toyo PCM, and run it all from the GM.

Steve

[joecar]

Cool...:cheers:...let us know how it goes.

[killalux]

Hey joe,
Another question, do you think it will go into a limp mode if it doesn't see the line pressure solonoid, TCC PWM solonoid, 3-2 shift solonoid or oil temp sensor? Or can these signals just be turned off, and leave the A, B, and TCC enable solonoids operational? Otherwise i may need to put in dummy resistors so that it thinks these items are there.

Thanks

[joecar]

Yes, the PCM might throw some DTC's...
you could try and see which DTC's are thrown, and in the transmission diagnostics/fault/max_pressure tables disable those DTC's.

Tho, it might be good to place resistors anyway (since the signals can't be disabled).

[Highlander]

Why not fit a GM trans?