Aisin transmission help needed

[plammer]

Hi all, first time posting here. I'm in the US and imported a 4JG2 with an Aisin 30-40LE from Japan (out of a 1994 Bighorn) which I've transplanted into a 1991 Trooper(Bighorn). The conversion has gone pretty well, but I've run into a problem of wiring the transmission computer (TCM). Since my Trooper was originally a manual and in the US only the GM auto was an option, I have practically no info on the wiring for the Aisin unit.

I have the orignal harness out of the donor vehicle and I've isolated the engine/transmission connectors as well as the TCM connector. The wires that are direct to the TCM are easy, but there are some unknown (to me) wires leading to the TCM and I'm not sure how to connect them. Here are links to what I've documented:

www.plammer.com/isuzu/wiring_stuff_PCM.txt
www.plammer.com/isuzu/Wiring_Stuff_Engine_1.txt
www.plammer.com/isuzu/Wiring_Stuff_Engine2.txt
www.plammer.com/isuzu/Wiring_Stuff_Engine_3.txt
www.plammer.com/isuzu/Wiring_Stuff_Engine_4.txt
www.plammer.com/isuzu/Wiring_Stuff_Tranny_1.txt
www.plammer.com/isuzu/Wiring_Stuff_Tranny_2.txt
www.plammer.com/isuzu/Wiring_Stuff_Tranny_3.txt

If you look at the first page, you'll see my list of wires to the TCM. Those with the ?? are the ones which I'm unsure how to connect.

Black I'm sure are just ground wires, two of the others have to be 12v power supply, I expect some are outputs like the power/winter mode lights, inputs like the power/winter mode switches, but without a wiring diagram I don't know which is which. Does anyone know how these match up?

I've searched for a wiring diagram that lists these, but I have had no luck so far. All the manuals/wiring diagrams have been focused on the GM auto transmission, nothing for the Aisin so far.

Any help would be greatly appreciated.

Thanks in advance!
Paul

[geeves]

there is a complete bighorn manual in the following gmail account and also a manual just on the auto.
go to www.gmail.com login as isuzunz pass 4jb1turbo Download the 11 ubs file attachments and put into a folder on your pc then download izark from a free software site like download.com. open the first file and you should have everything you need. If not there is a file with auto in its name but cant remember the rest. I have seen a pic of the tcm in one of those but cant remember which one.

[isuzumudman]

I think you will find little (even no) information about wiring loom stuff in the transmission manuals. You are most likely to find the wire colours and destinations in vehicle manuals under 'Chassis Electrical'. So, download manuals as Geeves suggests. The big plus is that they are searchable. Good luck.

[plammer]

Thanks for the replies Geeves and Isuzumudman, I just got back from vacation and downloaded them. Unfortunately they don't have the wire diagrams for the Aisin 30-40LE, only the GM 4L30E. I had downloaded that manual from another site as well and have done my best to use what I can from it. Unfortunately Isuzu seems to have not kept much in common between the wire colors between the 30-40LE and the 4L30E.

Might you have any other suggestions on where to find a description/wiring diagram that shows the use of the TCM wires?

I'm at a total loss at this point. The conversion had gone so well untill I stalled on this.

Thanks so much,
Paul

[geeves]

Look for the message AW30-80LE gearbox on the gmail account. This is from a toyota but its the same box

[plammer]

May 21, 2008 12:10:35 GMT 11 geeves said:

Look for the message AW30-80LE gearbox on the gmail account. This is from a toyota but its the same box

I forgot to comment about that one. I looked at that as well. It has a lot of good info in it, but unfortunately it doesn't contain the wire definitions. The only reference it has to the TCM is to disconnect it for a test.

I'm starting to wonder if I should just scrap the electronics and use it as a manually operated automatic. I think the band/clutch longevity will suffer, but I'm not sure what else to do. With this manual, I have all I need to rebuild it when the time comes

I'm starting to watch and see if I can find a Toyota unit with Toyota electronics. If that will bolt up, it might possibly be an option. It'd also give me the opportunity to find out if the Toyota electronics might be plug-n-play with this unit. From the Toyota wire diagrams I've looked at, they don't appear to be interchangeable, but maybe I could find something.

If you have any more suggestions, I'd love to hear them. I'm getting desparate.

Thanks again for the help on this!

Paul