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2015 Ford Explorer 1FM5K7F83FGB01843 ABS Activation on TURNS NIGHTMARE
Have you checked the steering angle sensor is reading correctly? If it's off the vehicle might think the difference in wheel speeds when turning is slip.
Can you post scan data graphed of the wheel speed sensors when it acts up? Also the pump motor command when it occurs. Did it do it before the rack was replaced??
1. make sure tires are same size and have the same pressure readings
2. scope each wss and make sure you have the scope settings the same for each one.
3. compare the waveforms they should increase in amplitude and frequency with speed increase.
4. time base should be set to 500 ms or 200 ms
5. 10 volt scale should be adequate.
6. usually in instances like this "like the one i am working on tonight" the one wheel speed sensor that is bad will oscillate less than a properly functioning one
the issue i have is random abs activation much like yours i do have scope files just pm me your email and i can send them to you Snapon scope files
Do all of the sensors look like that on the scope? Is there a gap issue with the sensor? Can you jump from a different sensor connector, at another wheel, to the ABS module to get a known good signal to the module? Unless they all look bad. I use that to rule out wiring after the sensor, to the module.
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