SW20 ECU in ST185.

[Adydas]

Has anyone tryed or can confirm simpley Will a SW20 Gen 2 ECU work in / with a ST185 3sgte?

[vvega]

yes it can be wired to work

[Adydas]

So that means a PFC for a SW20 will work to.. Wicked

LETS BUY ITT

[RomanV]

That could be an expensive assumption.

[Jebus]

Maybe get a stock SW20 ECU, try wire that up, if all goes well then get the PowerFC?

[vvega]

Maybe get a stock SW20 ECU, try wire that up, if all goes well then get the PowerFC?

im currently running a sw20 ecu in my 165......

its not a asumption

v

[fivebob]

Pinouts of the SW20 and ST185 are the same for the same revision of the ECU.

i.e. ST185 pinouts for production dates 10/89 - 8/91 are the same as SW20 pinouts for 12/89 - 12/91, and ST185 for 08/91 - 09/93 are the same as SW20 for 12/91 - 11/93

Part #'s that are share the pinouts are (all start with 89661 - );
ST185- 20750,20751 = SW20 17330,17331,17332
ST185- 2B280 = SW20 17380

The ST185RC has a different pinout, and would require approx 8 pins to be moved/deleted

[vvega]

lol im sure i read all that on mr2oc
in fact im sure it was you that posted it as well

[Adydas]

fivebob so vvegas wrong?

[fivebob]

fivebob so vvegas wrong?

Sort of....Correct in that it will work but kind of wrong in that you shouldn't have to re-wire(unless you have a ST185RC). Even that's not quite right because IIRC there's some additional wiring to fit the MAT sensor for the PowerFC.

Anyway for your reference (provided you can read Excel spreadsheets) the pinouts for the various ECUs can be found at;
http://www.users.on.net/~fivebob/Pages/3SGTE-PINOUT.xls

[vvega]

fivebob so vvegas wrong?

Sort of....Correct in that it will work but kind of wrong in that you shouldn't have to re-wire(unless you have a ST185RC). Even that's not quite right because IIRC there's some additional wiring to fit the MAT sensor for the PowerFC.

Anyway for your reference (provided you can read Excel spreadsheets) the pinouts for the various ECUs can be found at;
http://www.users.on.net/~fivebob/Pages/3SGTE-PINOUT.xls

he has a 185RC (pokes tounges)



v

[Adydas]

Just so i understand, the Loom or the ECU its self need " Re Wireing "

[Malcolm]

wiring loom needs to be changed to suit ecu. If it's a matter of 8 or so pins being different that's a pretty easy task, just remove the pins from the back of the plug and swap them to the correct spot (or cut + solder/crimp if the plugs are different)

fivebob - where were your RC pin out diagrams 3 years ago when I was looking for them!?

[fivebob]

wiring loom needs to be changed to suit ecu. If it's a matter of 8 or so pins being different that's a pretty easy task, just remove the pins from the back of the plug and swap them to the correct spot (or cut + solder/crimp if the plugs are different)

Plugs are the same as are most of the pins, there seem to be a few extra ones on the RC loom, which can probably be left alone, but there are a couple which may be necessary and the SW20 loom does not have them.

RC has EVP, ISCV, RLY and ECO as extra pins. EVP is catered for on the Gen III so the PowerFC should support it. The others may not be needed but I'd be worried that ISCV (Idle speed control valve?) and RLY (??) might affect the running of the engine.

The SW20 has PS as an extra pin, but that's just a signal to the ECU when the PS is runnibg so it shouldn't be a problem.

Pin differences;

ST185 has WIN pin where the SW20 has an ABS pin, not sure what either pin is used for (input/output?) or if they're required. My guess is that The ABS pin is not needed on the ST185 so the ECU will still function correctly, but I don't know if WIN signal is an output and may me needed, or an input and therefore not required.

ST185 has ATS pin where the SW20 has a PSCT pin, PSCT is not needed on the ST185 and shouldn't cause an issue, don't know what ATS does so I can't say if it's needed.

fivebob - where were your RC pin out diagrams 3 years ago when I was looking for them!?

On my computer, and on the Japanese website where I found them

[Malcolm]

fivebob - where were your RC pin out diagrams 3 years ago when I was looking for them!?

On my computer, and on the Japanese website where I found them

You need to make a post with links to all extremely useful bits of information in it, for me to look through whenever I need to find info on stuff. Would have also been quite useful when I wired an st185 RC loom/computer into my friend's 165 a few months ago.

ST185 has WIN pin where the SW20 has an ABS pin, not sure what either pin is used for (input/output?) or if they're required. My guess is that The ABS pin is not needed on the ST185 so the ECU will still function correctly, but I don't know if WIN signal is an output and may me needed, or an input and therefore not required.

From the above experience, I can tell you that on the RC the WIN pin goes to the water/air intercooler ECU, and if it's not connected to anything it causes the ECU to throw code 54, which I now believe just means that the intercooler computer has found an error (no pump, low water etc), which it reports back to the ECU by opening the a circuit which normally connects WIN to ground. Code 54 was eliminated by simply grounding the WIN wire.

Whether the intercooler computer gets any information via WIN, such as when to turn the pump on and off, I can't comment on as we ditched the intercooler ECU and ran the pump full-time.


Just looking through the pin-outs I realised something perculiar - the Japanese Gen 2 ECUs don't have the STJ pin, which IIRC is the cold start injector. Is this because the JDM cars had the CSI controlled by a switched power feed running straight from a +12v source and through a timer/temp switch?

[vvega]

yeap i have no cold start injector workin on my car right now
its quite the c**t...prolly just going to add a button for it

i belive the" rly" is the output to control the pump
its bascially a ecu controled switch based of throttle position

as said the win is for the error senseing normally ground for intercooler ecu

evp is quite posiby not connected on cliffs car as it should be the EGR valve position sensor ??

ATS is air condidtioning amplifier

ISCV is idle speed control valve\\

i belive teh rc has a differnt idle control valve as normally you only ISO and ISC or you will have a RCV with numbers listed dependant on the stepper

ie the 1uz has rsv #1 though 4

i hear though a man that might attually know that teh rc might use teh tb return line as a bov of sorts
though i cannot confum this so its pure speclation



v

[Malcolm]

i belive the" rly" is the output to control the pump
its bascially a ecu controled switch based of throttle position

I don't think it is, the intercooler ECU controls the operation of the pump and there is only one wire going from intercooler ECU to engine ECU and that's WIN.

evp is quite posiby not connected on cliffs car as it should be the EGR valve position sensor ??

There's a small VSV by the charcoal cannister on the RCs which is probably connected to EVP

[fivebob]

There's a small VSV by the charcoal cannister on the RCs which is probably connected to EVP

That's what it's usually connected to, the Evaporative emmisions system. The Gen III has the same thing and seeing as the AP engineering PFC is based on the Gen III version, it should still be there.

[matt dunn]

i belive the" rly" is the output to control the pump
its bascially a ecu controled switch based of throttle position

I don't think it is, the intercooler ECU controls the operation of the pump and there is only one wire going from intercooler ECU to engine ECU and that's WIN.

I have a toyota training manual here from when dad was at toyota about the toyota turbocharger and supercharger systems.

It has the diagrams of the toyota GT4 Water-air system.
It shows there are two wires from the engine ecu to the
intercooler ecu labeled as IDL and WIN.
Then there are three other wires to the Intercooler ECU,
Ign, Motor earth ( there must be a relay inside the int ecu)
and earth, and the coolant level sensor.

Is says WIN stands for "Warning Lamp, Intercooler"

The manual is from the early ninety's so doesn't have all the new generation stuff in it.

Matt

Matt

[Malcolm]

well there you go - when I was tracing wires on the RC body loom I only saw one that went into the engine ecu from the IC ecu, but I guess one of the others that ran into the engine loom must have done a U turn back to the engine ECU.