Conditions for Clearing MIL/DTC

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2002 GMC Savana Special, 2002 GMC Savana Camper Special, 2002 GMC Savana, 2002 Chevrolet RV Cutaway, and 2002 Chevrolet Cutaway. However, it is still accessible from the selected car via links, so may be relevant.

A History DTC will clear when 40 consecutive warm-up cycles, during which the diagnostic does not fail, coolant temperature has risen 40°F (5°C) from the start up coolant temperature, and the engine coolant temperature exceeds 160°F (71°C) during that same ignition cycle.
A scan tool can clear the MIL/DTC.