Anyone know exactly how to hook this computer (2000 s10) up to a diagnostic port so that I can write a tune to it? There are 2 serial data lines and I cant find any wiring schematics on how to wire them up. Please help Thanks. All I can find is f-body diagrams and they only have 1 serial data.

 

Use the dark green on pin #11 of connector C4
The other one that is yellow on Pin #14 goes to the BCM

 

There is no BCM it is going into a standalone project. So would I just not worry about the yellow one?

 

that's correct.

 

 

ok, Im at the computer and I tried the green wire but its still not working. I have a purple one and a green one and neither of them are allowing me to write. They both time out on ERASING VCM. Here are 2 screen shots and the file Im trying to write back to the computer. Only change made is disable VATS so that I can get this engine running.

 

Pin 11 on the black plug is a serial data 2 wire except I still cant write to the computer. Get a timeout error.

 

You do have ground and power, right?

 

pic of license info

 

Yes power and ground are good everywhere. Like I said I can read the VCM ALL DAY and pull the tune from it, but when I try to put a tune back onto it I can't. Every other VCM I hooked up to I was able to read and write. This is the first one giving me these problems.