Most places will tell you to try to track down each abs speed sensor connector, but really, you can just check all sensors right at the ABS computer module. To get to this module and plug only takes removing 3 half turn screws.
With a multimeter you can check resistance on connector pins:
4 and 6 for LH Front ABS speed sensor
21 and 11 for RH Front ABS speed sensor
8 and 9 for LH Rear ABS speed sensor
24 and 26 for RH Rear ABS speed sensor
The resistance should read about ~1000 ohms across all sensors, some deviation is okay, but normally a failed sensor will be substantially different than the others.
Consider also replacing all ABS relays for best longevity:
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This is very helpful–Thank you!
I’ve been told by a reliable source that sometimes crumbling sensor wires will cause the pulsating or perceived failure of the ABS system. Has anyone encountered this?