Code 25, Code 26, Code 27, Code 28: Wheel Speed Acceleration Fault: Notes
Each wheel speed sensor generates a signal which is proportional to wheel speed. When ABS module detects speed signal change greater than 10 MPH while vehicle is moving, it disables Anti-Lock Brake System (ABS) and illuminates ABS light. See Fig 1 .
Code will set if wheel speed signal changes by greater than 10 MPH in 8 milliseconds. This code can be set any time vehicle is moving and not in ABS braking. Code 25/26/27/28 may be set together with Code 21/22/23/24. Drive vehicle faster than 40 MPH to check for reappearance of failure.