Wheel speed sensor or abs magnetic ring?

[csak1981]

Just had abs vsa and cmbs lights come up on dash. I stopped and switched off then back on then it's fine. Plugged computer in and I'm getting
"Left front wheel speed sensor malfunction" in abs module as well as "Brake prohibition" fault and "VSA modulator malfunction" fault in another two modules. I've seen the latter two come up before when I had a different problem with my original abs pump motor module. I've learned any problems with abs usually logs these other two fault codes and so all three lights will show on dash. Even though it's just the abs module with an issue then once resolved they will all disappear.
This second abs module had been fine for the past year it's the wheel speed sensor fault that is new so I'll probably start there. Does anybody know if I'll get lucky just changing it or is it likely to be the abs magnetic ring on the wheel bearing at fault and also will an aftermarket sensor be ok if so which brand to go for or is it oem only

Cheers

 

[mlkehunt]

inspect wiring near the brackets, 7th gen is probably worse for this where it mounts on the upper wishbone but it may be worth a shot if it's intermittent and you can log wheel speed without dips or spikes
white wire on mine was split/splitting on both fronts without any clues from just looking at the insulation, but you can feel it if the copper is split

 

[Channel Hopper]

I found the original sensors with the car had fallen apart through age, there is athread about drilling out the debris and cleaning the interior on the site.

A replacement sensor later on turned out to be out of spec and the ECU would not read the pulses correctly.

No issue with the magnetic ring on any hub after 190k, which is good.