Conditions for Clearing the DTC

WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, and 2009 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

A last test failed, or the current DTC, clears when the diagnostic runs and does not fail.
A history DTC clears after 100 consecutive warm-up cycles, if failures are not reported by this or any other emission related diagnostic.