So i wake up this morning and hop into my truck and i notice that the abs lights dosent go off after the dash diagnostics is complete. So i turn off the truck and then back on and it stays off until i start driving, and then bam its back on again. My first guess is that the pads are worn down and need replacing, but i wanted to check if this is a common problem with the computer or a sensor or something like that.
oh yeah here is the vehicle stats,
2000 Ford F-150 5.4l V8 xlt 2wd automatic with 148000 miles.
Front brakes are under 40 thousand miles the rears i dont know. any info is appreciated.

 

The system has detected a fault in the system and illuminated the light. Normal braking is fine, but the ABS system is disabled with the light on. The most common culprit is the ABS sensor on the rear diff, but without pulling the ABS codes from the system, there's no way to know for sure.

-Joe