Conditions for Clearing the MIL/DTC
WARNING: This page is about a different car, the 2002 Oldsmobile Bravada, 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
The PCM turns OFF the malfunction indicator lamp (MIL) after the third consecutive trip the diagnostic has run and passed. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction. The DTC can be cleared by using the scan tool Clear DTC Information function.