Does anyone have the Axxess usb-cab cable used to upgrade Axxess wiring harness interfaces? If so could you tell me what pins on the usb standard connector are mapped to pins 2 and 3 on the small white connector? I assume that the red is positive and the black is negative. That leaves the orange and yellow in the middle. One is positive and the other is negative. If I can find out which is which I can make my own cable instead of having to buy the $80 one because the software is free to download from their website?

Did you ever find the pin mapping for the Axxess USB-CAB. I need one to update the firmware on my steering wheel controll so It will recognize my deck.

It's not actually a direct USB cable - it's a TTL (serial adapter) cable. The trick circuit is in the plug at the USB end.

You can obtain a USB TTL cable for ~$20 from outlets such as Mouser or Digi-Key - the model is TTL-232R-5V

According to others who have successfully used this cable, the pinout, starting from the inside of the XIA or AHDI unit, is Black > Yellow > Orange > Red and you leave the rest of the wires loose. (TTL cables have 6 pins)

This matches the photo of the USB-CAB found on Axxess' website.

I'm still waiting for some parts to arrive before I can try this for myself, but I am confident enough in this information to attempt it with my system.

If it's worth $30 to have someone else pin it out for you, the actual cable is now selling for under $50 from several online retailers.

UPDATE: I tested the setup described above with an XIA-I01 and I can confirm it does work perfectly. I used the software available for download on Axxess' website and it performed without any error or difficulty - even the plug on the TTL cable fit the pins on the XIA, so I didn't have to place them one at a time.