I have had this problem before and replacing the distance sensor solved the problem. So naturally I did that again this time but the problem persists. I have tested both the old and new sensor they both are test good with 8 open close intervals per revolution. I've checked for continuity of Or/Wt to the dash and navagation unit, as well as to the smec, all is good. The Bk/Lb also tests good for continuity. The only thing that I found strange is that Or/Wt does not have infinite resistance to ground. It reads at like 1700 ohms. But then I tested Or/Wt as a ground and with red probe on positive of battery and black probe on Or/Wt from the distance sensor, And it read 12v.
So then I pulled each connector that Or/Wt goes to and in each case the resistance went up, but I could still read 12v like I did before from each individual connector. Is there normally some continuity to ground on a feed line? All other sensors work fine. The other thing I noticed is that when OR/Wt is to ground the speedo stays at zero. Its only when the line is open that it goes crazy.