Diagnostic Aids

WARNING: This page is about a different car, the 2019 GMC Savana 3500, 2019 GMC Savana 2500, 2019 Chevrolet Express 3500, and 2019 Chevrolet Express 2500. However, it is still accessible from the selected car via links, so may be relevant.

Inspect the knock sensor for physical damage. A damaged sensor may cause a DTC to set.
The knock sensor mounting surface should be free of burrs, casting flash, and foreign material.
Tightening the retaining bolt too much or simply dropping the knock sensor on the ground can damage it.