Alternative/cheaper ECU patch/test harness

[PhyrraM]

While browsing sround trying to troubleshoot my SVX A/C (of all things) I came across a Ford service tool that can be used as a ECU patch harness for our 4 plug ECUs (EJ22, EJ22t, EJ20G, etc).

It is Ford/OTC part number T96P-12A650-B.

It is meant as an interface between Mazda built Fords and the official EEC-V (Ford ECU) breakout box. Basically it allowed Ford tools to be used with Mazda ECUs. Many asian ECUs used the same 76 pin connector as our cars.

I paid about $12.00 shipped. I seem many more on eBay for less than $40.

Below pictures should tell the story. Also a picture of it plugged into an EJ20G ECU just to show the connector is the same. There are many ways to use it, but between cutting the wires, the Ford connector, and even desoldering and replacing wires the options are pretty limitless for those of use who refuse to cut our harnesses. Size seems to be the only disadvantage to the $130+ versions (AEM, etc)
















Hopefully this helps somebody. In addition to hacking as a patch harness if you pair it with a Ford EEC-V (104 pin) breakout box it could make for very convenient plug-n-play ECU and signal testing once the pins are cross referenced.

[Legacy777]

That is an AWESOME find!

I'm going to put this in the sticky.

Thanks for sharing!

[cj91legss]

Wow, that's awesome!!!

[demetricleas]

Is there a way to merge this with the wiring in a stock ej22 to work with the turbo ecu

[kimokalihi]

Good to know Jess. Nice find. If there's other vehicles out there that use the same ecu connectors, perhaps there is also a cheaper patch harness that's similar to the aem one that costs $130.

[Alphius]

Good find!

DIYAutoTune has the DIYBOB for the Nippon-Denso 76-pin connectors that these cars use. They have an application list on their site showing many other US market cars that use the same connector. The DIYBOB includes the reverse connector necessary to construct a patch harness without sacrificing an ECU for parts.

Application List:
https://www.diyautotune.com/support/tec ... re/diybob/

Breakout adapter:
https://www.diyautotune.com/product/diy ... so-76-pin/

Mike and I had thrown around the idea of making a Plug-N-Play style MegaSquirt kit with included basemaps for these cars using this part. I've always wanted to do it but haven't had a car available to use as a proof-of-concept.