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

[WannabeGT4]

I was curious about the mark up on this so I did a little research. These are the part numbers and prices from Toyota:

26 Pin Connector
90980-11390 $5.09
?alt?90980-11423 $5.09 ?alt?

22 Pin Connector
90980-11392 $5.06
?alt? 90980-10765 $5.66 ?alt?

16 Pin Connector
90980–11391 $5.07

Not 100% sure about this one since it didn't have a picture:
PCB Connector 64 pin
90980-11576 $8.52

The terminals that go inside each connector are easily obtainable from places like mouser.com or digikey for pennies a piece. The terminals with wires pre-crimped are also available from Toyota but without some in front of me I couldn't tell which ones they were.

The $199 price tag must be in the time it takes to assemble... which, with the proper tools shouldn't take too long at all. You've got a very profitable product there Dr. Tweak, as long as there is a demand for it.

[Dr_Tweak]

That's a ridiculous idea. I don't expect him do give anything away. I expect that when I offer an alternative he addresses the situation as a professional and not resort to name calling. A discussion about price and demand for the product should never have escalated into what this has become.

Let's see, you come into a thread where I am offering a product, decide your "curious about the markup" and then proceed to attempt to present evidence that I am making these for less than $25 each and am therefore marking them up 800%.

What exactly IS your motivation for doing that? Really, why go through all the effort? Have I done something in the past to upset you or something?

-Doc

[WannabeGT4]

That's a ridiculous idea. I don't expect him do give anything away. I expect that when I offer an alternative he addresses the situation as a professional and not resort to name calling. A discussion about price and demand for the product should never have escalated into what this has become.

Let's see, you come into a thread where I am offering a product, decide your "curious about the markup" and then proceed to attempt to present evidence that I am making these for less than $25 each and am therefore marking them up 800%.

What exactly IS your motivation for doing that? Really, why go through all the effort? Have I done something in the past to upset you or something?

-Doc

My motivation is to provide a DIY point of view. What would the average hobbyist be saving if they decided to do it themselves. There really was not much effort involved. I had the .pdf with part numbers and it's just a few clicks to find prices.