Question

2002 Pontiac Aztek with code C0051, what is this code for? How can I fix it?

Answer 1

C0051 wheel speed sensor

This code is for the ABS system , you would use a scan tool that can read each wheel speed sensor and inspect the one that deviates from 10 MPH, In very rare case a wheel speed sensor that was replaced and the fix was not resolved the problem was with the EBCM, as the ABS unit replacement was the fix

Answer 2

C0051 PONTIAC Code - Right Rear Wheel Speed Sensor Circuit Range Performance
Read more: https://www.autocodes.com/c0051_pontiac.html