wheel speed sensor/ABS issues

[Bobo]

Was driving the other night and got a 'service advancetrac' warning on my 2015 Fusion Hybrid SE.   Then the 'hill assist not available' warning, and then the traction control light, stability light, and ABS lights came on (oh, and the airbag light).

So I came home and did my due diligence online.  Looks like wheel speed sensors have issues.   I drove up to autozone and used their tool to scan.  Came back with:

invalid signal for right and left front wheel speed sensors
Vacuum supply - signal plausibility failure 
Battery Voltage -Circuit voltage below threshold.
Right front wheel speed sensor - signal erratic
Right front wheel speed sensor - mechanical failures

So I brought it home, popped the wheels off and did a couple of things.

1. I read about a service bulletin regarding the wheel speed sensor wiring having corrosion issues.   So I took off all the tape and examined the wires.  Everything looks fine, no breaches.
2. Then, after having a BITCH of a time getting the wheel speed sensors unhooked from their respective harnesses (wtf designed these harnesses?  I'd LOVE his phone number!) I swapped out the drivers side wheel speed sensor with the passenger side.  I figure, I'd take it back to the zone, check it again, and if the right and left codes had switched, it would tell me if i had a bad sensor.  

Had it scanned again, and had the SAME report, with the exception of one NEW item

Right front tone wheel - mechanical failure

Okay.   So there's something I didn't mention.  When I was removing the wheel speed sensor from the right front wheel, I noticed some tulle, or fishnet, or some kind of  light fabric kinda bound up around the sensor.  I unwrapped it and tossed it aside, figuring it's just wrapped around the sensor, and that shouldn't hurt it.  But then I started thinking, what if that little piece of fabric is only a PART of the fabric I picked up somewhere.  Might some of it have gotten pulled into the rotor/hub area?  Could a piece of this fabric be 'gumming up the works' where the tone wheel and the wheel sensor meet?

So that's where I'm at!   What I'm wondering is, just how different are these hybrids from their non-hybrid counterparts in this area?   I do not have the service manual for this car, so I don't want to screw up anything.  I cannot see behind the rotor shield to look in there.  I have a boroscope, but even it won't fit.  Can I remove the caliper just like I would on any other vehicle and gain access to at least SEE behind that rotor shield?  These things having regen braking and all, I don't know if there's something I don't know about that might screw it up.

Also, my brake pads look GREAT considering the car has 130k on it!!!  Gotta love that regen braking!

Any help or pointers you guys could give would be fantastic!

Edit:  Well, I just realized the driver side and passenger side sensors are different.  Probably why there's a tone ring failure now....
I'm assuming that even if I switch them back and the tone ring is working again, that I'll not know it because the code will still be there.  I'm guessing the only real option I have now is to get to the tone ring to examine it.

Edited July 13, 2021 by Bobo