Conditions for Running

WARNING: This page does not describe the selected car, but rather 13 other vehicles, including the 2003 Hummer H2, 2003 GMC Yukon XL, 2003 GMC Yukon, 2003 GMC Sierra, and 2003 GMC Cab & Chassis Sierra. However, it is still accessible from the selected car via links, so may be relevant.

DTCs P0442, P0446, P0455, P0496 are not set.
The barometric pressure is more than 75 kPa.
The fuel level is between 1/4 and 3/4.
The battery voltage is between 10-18 volts.
The test will initiate only after a cold start. The control module considers the engine to be cold if the following conditions are met:
1. The Engine Coolant Temperature (ECT) is between 39-86°F (3.8-30.0°C).
2. The Intake Air Temperature (IAT) is between 39-86°F (3.8-30.0°C).
3. The difference between the ECT and the IAT is less than 14°F (8°C).