This is the wiring harness that I bought for the Mazda.
Now I hooked up all my wires from the Kenwood to the harness fine. The big antenna cable is connected too.
I only have my ground wire left.
Now from the car there is left a small cable that looks like a mini antenna plug in. Me and my dad tried to see what they are by unpluggin the first then the second whne the stock stereo was in...if both are out...no radio..if either one is in radio is there. So forget about the small antenna cable, we should be fine without it.
We did the same with the small little black clip in cable without it there is no power to the radio. Now I'm sure it's not the actual power cable because on the wiring harness there was a specifically designated cable for power!
This only leaves it to be a ground cable because usually on stock stereos a metal wire that just screwes on to the back of the stereo (or something like that. that's the way it was on my concorde stereo). Here there was nothing close to ground except that because without ground the player shouldn't work right?