Conditions for Running the 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 engine is running.
The system voltage is greater than 8.5 volts.
The intake air temperature (IAT) is greater than -7°C (19°F).
Zero percent duty cycle is commanded, and the engine RPM has been over 1800 RPM for at least 120 seconds.