thanks for a great guide and pulling together these documents. Very helpful. I put together my G5 in 2008 and had to mod my cable with a multimeter and wild guesswork.
Never really got beyond power switch and LED, as the front connectors weren't a major concern at the time, but recently revisited it and decided to make a new clean cable. this guide made things much clearer. However:
1. I decided to avoid soldering cable to cable, and instead gently pried pins from the G5 connector, removed the wires to give me bare pins, then recrimped and soldered new wires to the pins. added header pins at the other end, so that I had clean one piece cables end-to-end. pushed back into the connector, it leaves a perfect looking cable.
However, when hooked up, power and led still work but firewire and usb (EDIT: USB now working fine. May have been bad test) do not. Checked and double checked cable pin to pin and used diagrams for pin outs, and still nothing. Could my choice of wire be an issue? I've read that firewire is picky on cable impedance, but sounds like you guys have had success with simple header wires and soldering so why no joy for me?
2. As a test I went back to my old (spliced) cable, and tried wiring in some front panel cables I had. Still no joy on firewire. Which makes me think either the cable is an issue, or i'm missing something in my wiring...
Anyway, thanks for the guide and if anyone can think of a way of diagnosing my issues, let me know