I'm sure to get flamed, but here goes...after much searching I am desperate.
connecting a MTXL to my DIY PNP, I don't know where to connect the signal wire. I had once found a picture of the db15 connector with labels to the wires, but can no longer find it. my db 15 plug has a bunch of orange wires without any designation. I have a braineak built unit and a '95 1.8.
sorry for typos, my eyes are bleeding from typing every search I can think of related to this.
Thanks

 

The signal from the MTXL replaces that from the narrow band O2 sensor.

Look along the edge of the main board where all the wires from the OEM harness connector are going. One of them says "O2 sensor" or something like that. Unsolder the wire that's in that hole and replace it with one from the MTXL.

The 15 pin connector is normally free to do whatever you want. In other words, pick any available pin and use it to get from outside the box to inside. I don't know what Brain has already hooked up.

 

Perfect. Thank you. Yesterday, I did a bit more searching and was able to locate the signal wire for the factory 02, then juts tapped into it with the stock narrow 02 disconnected.

 

I almost always include the diagram in the box and/or email.

it's possible that you wont have an o2 signal if you connected your wbo2 in that manner.

 

I purchased the unit used on this forum, so I didn't get a diagram of any sort. I am getting a good 02 signal though.