Hi again
Sounds like you are going through exactly the same sequence of events that I did. Dont forget to get the flashing ABS light when you spin the wheel, you must go through that sequence of retrieving the fault codes, clearing them and leaving the ignition on. Once you have verified that the front light flashes when you spin the front wheel and that the back doesn't flash, you can verify that it is the sensor and not the wiring by putting the front sensor on the back. and re-checking. My guess is that the fault on the back wheel will disappear, and the rear sensor on the front wheel will not then produce the flashing. That symptom could still arise with a fault in the connector or in the short lead to the sensor. But so far it sounds like a faulty sensor. Ron Ayers has one listed at $165. 38510-MAJ-781 (or 780). Dont take my word for this code, please check it yourself !! David Silver also has one listed but its over ?200. But first you need to see that flashing ABS light when you spin the front wheel. Drag a neighbour in, or get a mirror rigged up. Or a video camera, and look at the replay.
There is an awkward little clip on the front sensor cable which is difficult to work out how to get it off. The clip pivots on its fixing, and I spent ages trying to undo the pivot, which wasn't the right thing to do !
Like you, I didn't want to splash out on a sensor and then find it was something else. Once I had the two disconnected and was able to compare them side by side, I was certain. You will NEVER get the code 6 fault code again. The ECU checks that both wheels are turning by the same amount before it arms itself. If it doesn't arm itself, then it cannot record the fault with the sensors. So the symptoms you have, coupled with the previous code 6 definitely point to the rear sensor or rear sensor wiring.
Do your sensors come out of their brackets easily ? I only ask because my rear one didn't. I'd had it out 6 months previously, but it was locked solid. I soaked it in penetrating fluid, and got a very narrow bladed screwdriver and tapped it gently between the bracket and the flange of the sensor, thinking that the narrow wedge shape would lift the sensor out of the hole. It didn't. I was ever so careful, but the oh so gentle taps transmitted to the bracket, and the cast alloy bracket snapped off. I had to replace the entire backplate and bearings to get the ABS working again. I'm saying this to emphasise how fragile that back sensor bracket is. I've always liberally greased the sensors since then (although the 1300 sensors have a seal and a MUCH bigger space between sensor and hole.
But I did locate a sensor at a breakers yard. They seem to be the same type from 1992 to 2002 - but again, check this out for yourself - so you stand a chance of finding one. And in my case, the breaker hadn't got a clue what he had got - he let me go through his entire ST1100 bins looking for one - in the end I found one lying on the floor. ?10.
There is a clip which holds the sensor cable on the swinging arm near the drive shaft universal joint. I had trouble with that. Its a long time ago now, and cant remember exactly, but my hands are massive, and cant get into tight spaces easily. I got the cable out OK, but I seem to remember having difficulty threading it through the gap and resorting to taking the wheel out to get it back into place. You may have more luck.
