Using a '93 3SGTE ECU on a '91 3SGTE Engine and Harness Options

[Dr_Tweak]

Some weeks back I had a customer doing a 3SGTE swap into a '91 Celica that I did a wiring conversion for. After he got it back and installed, I asked him for the part number on his ECU since I've seen many situations where the importers send the wrong ECU for the year of the harness. Sure enough, he had a '91 Harness but a '93 ECU. I advised him to get a '91 ECU, but he was having a hard time locating one.

About the same time, I started gathering parts and doing research for making jumper harnesses for various Toyota applications. I located the supplier for the female ECU plugs for a few different Toyota harnesses. When I got one in that matched the 3SGTE harnesses, I though, why not make a jumper harness that goes from a '91 harness to a '93 ECU, or a '93 harness to a '91 ECU? Then customers who run into this situation don't have to find another ECU or repin the whole harness.

Since I had this customer, Bryant, who had this very situation at hand, and since I happened to be going near where he lived on a recent road trip, I decided to whip up a prototype and give it a try.







There it is plugged into a 3SGE ECU as an example. This first one came out a little rough, the production model will be cleaner.

And here it is plugged into the car:



The jumper harness worked PERFECTLY. It fired up the first try and is running great, no codes and no problems at all

If anyone wants one of these jumper harnesses let me know, I'm currently building them to order.

Other applications for this setup include plug and play jumper harnesses for standalone units that don't already have a plug and play setup, like perhaps 3SGTE/Autronic, and so on.

-Doc

[Dr_Tweak]

How much? $7 each or something?

So if you aren't going to use those, how will you get the pins?

-Doc

Yeah that was his price locally. Online they're about $3.38 each.

Small terminal with wire
82998-24020

Large terminal with wire
82998-24100

digikey or mouser would be where I'd start.

Yes, but even if you could locate the correct pins, HOW would you connect them to the wire? Ours are connected using the OEM TYCO crimp tool which is several hundred dollars EACH (yes, you need a different one for the larger pins vs the smaller pins), so we know that's out of the question since that would automatically put the cost too high, and I KNOW you aren't going to try to ghetto-crimp those pins using some "general" crimping tool.

hey Doc if you find out how to st185-st205 let me know!!!
i'll get a jumper & get rid of my vpc.
We need more choices like honda guys, why should they get to mix & match and we cant...

you go DOC!!!

I can do it no problem, just let me know what your ECU part number is and keep in mind the other things you need to swap to a 3rd gen ECU.

Woooow.

I think Doc Tweak is a real asset to this community (as well as others) and the prices of his products are his determination of parts, labor and DEMAND; which I have not seen mentioned. There's a reason that PS3s and Wiis were double or triple the MSRP because of demand alone.

If you think the price is unsuitable, you don't need to buy the product; and creating an open-source in an alternative is acceptable, but this sort of thing is ridiculous.

BTW: Doc I recommend you all the time.

Thanks Supersprynt Actually I will readily admit that the demand is very low which is why these are prices so reasonably. I already serve a very narrow market in the automotive community and these jumper harnesses only appeal to an even more minute number of people. Actually, the only real interest that has been expressed in these has come from other shops that do a lot of Celica/MR2 stuff, because it's much more cost effective for them to just buy a jumper harness rather than "dick around" with rewiring a harness on their own or spending a couple hours on the internet looking for a good price on a new used ECU.

-Doc

This post has been edited by Dr_Tweak: Jan 3, 2008 - 9:04 AM