Tried making own Serial Wideband Cable, HELP!!

[edwardzracing]

I know I'll probably get crap for this, but that's okay... I'm just hoping someone can help. I managed to try using a DB9 male to male converter instead of a male to male Null Modem, and of course it didn't work. So instead of waiting to buy one, I cut into my cables to try and make my own. I got into the RJ12 cable from EFILive, and found the 1, 2, and 5 wires... black (1), red (2) and brown (5). Okay, good deal. I got into the serial cable that came with my LC-1, and there's only a black and red wire... no white wire like the illustration here (http://forum.efilive.com/showthread.php?t=8115)

So I'm wondering if anybody knows if I were to buy like a 2.5MM phono jack from like a radio shack or something would it have the 3rd wire I'm magically missing?? This definitely sucks as I do not want to start my car until I know for sure I have my wideband talking to my FlashScan. Any help would be greatly appreciated. Thanks guys.

Brad