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

[Gary]

I used to make these adapters. I sold one for $50.
And trust me, I will never sell them at that price again.
It just doesn't worth 2 hours doing it.
Soldering almost 50 wires onto those pins that are 1/8" apart is royal PITA.
Then again, if the adapter costs more than an ECU price, most people will just go buy a new ECU.