ABS light came on . After several off and on movements with switch light went out for about 100 miles. Came back on and then went out on its on for 20 miles then came back on. Checked fuses for ABS. Had truck scanned. Scan says all three sensors are bad. Don't think all three would go bad at once. Cleared codes and left shop. Light immediately came back on. Checked continuity from sensor to module (disconnected plugs on fenderwell and rear axle prior to continuity check). All six wires are good. Next Step?