92 Lexus Sc400 40/40/40 wiring diagram?

[tyes]

I've been looking everywhere on the web and unable to find the right pin-out and the wiring diagrams for this 1uz. I'm getting a little frustrated. I've searched for 3 days now and found a pin-out on some site that might work but not so sure. I've viewed all the wiring diagrams on this forum but still not sure. Since this is my first wire up, I need something more solid than "it might work"..Its a 92 Lexus SC400 Automatic Transmission with 40/40/40 pin, part # 89661-24240 USDM ECU. Can someone please point me to the right location to get this? My swap is going in soon and I want to get this sucker organize. Its going into an 86 4Runner 4x4. Thanks in advance.

 

[Vate]

Here's a couple of pages that give the pin outs for that version(attached).
I spent many days searching the net to find them, so enjoy.

Here's the location links to the full wiring Diagrams of this ECU already on this site:
http://www.lextreme.com/PDF/scecu1.pdf
http://www.lextreme.com/PDF/scecu2.pdf
The two 40-40 plugs that are joined together are read on these diagrams as No's 1 to 80. You can see the way it is numbered on the attached pages.
When I was first looking for diagrams for this ECU, I didn't realise these diagrams related to the 40-40-40 unit. You need to study it more....

Cheers

 

[Vate]

Here's a PDF file I made up that may make it easier. By memory, it all worked out okay, but when you wire it up, double check with the other diagrams to ensure I have it right. I just about drove myself mad researching to get all this right, so once again enjoy....

Cheers.

 

[samsdad]

Vate you're pretty much on the money but MREL goes to the earth side of the main relay or as you've found you can't turn the bloody thing off (made that mistake too). I used the ecu pinouts and also the wiring diagrams here on this site when I wired mine up 5 years ago. Since then however I have managed to get my hands on the factory wiring diagrams.

If it is planned to run the factory auto then the P,R,D,2 and 1 inputs from the gear position indicator (inhibitor switch) will need to be hooked into the ECU to avoid weird up and downshifts esp to 2nd gear

 

[samsdad]

Further to post with the auto the O/D and K/D switches will need to be fitted on these one side to ECU and other to earth, also the O/D off light will be needed as this is used to diagnose any faults in the ECU side of trans control

 

[tyes]

Thanks guys!!! This is really going help out identifying wires correctly. I was pretty bummed last night after I posted this, but now I'm motivated.. Thanks! For the guys who had done this wire up, do i just cut all the additional stuff like ABS, TRAc, Cruise control, etc, off the core wiring harness? Im in california and will be dealing with smog issues.. They are particular strict on check engine lights...

 

[BossEng]

Vate you're pretty much on the money but MREL goes to the earth side of the main relay or as you've found you can't turn the bloody thing off (made that mistake too).

I currently cant turn my engine off, and its because M-rel is staying LIVE +12v......

M-rel puts out +12v and the other side of the relay goes to earth, it turns the relays on just fine, but once the car is running, it wont shut down

but, by what you are saying, my relay should have +12v sent to one side, and have M-rel on the other? Surely the relay wouldnt turn on then?

 

[Doubledip]

mrel is def a + output
and when u turn ign off mrel stays on for 2 or so seconds
this is y u must wire up the power to ignitior and injectors directly to ignition key
or thru a relay control by ignition key
this way if ecu stays on the key cuts power to injectors and coils and engine stops
99% of these problems are wiring problems caused my the man with the soldering iron and diagrams or sometimes its due to wrong diagrams
mrel is very easy to test
put ign to igsw wire and test for 12v on the mrel wire when not connected
remove power toi igsw wire and u should loose 12v at mrel wire so if this works ok
then yr wiring is sort of ok if not the you have the wrong wire for mrel
there is afew tiny differences between some ecus

 

[litldv8]

so m rel goes to the earth side then even though it is a 12v pos output?

 

[BlackUZZ31]

here is one I did...

https://docs.google.com/spreadsheet/ccc?key=0AriRGOSISQe7dFRPUVR5YXpEdnJhYV96S0dDb0VyeWc&usp=sharing

 

[litldv8]

so to the ignition switch it goes