Actions Taken When DTC Sets

WARNING: This page is about a different car, the 2002 GMC Savana Special, 2002 GMC Savana Camper Special, 2002 GMC Savana, and 2002 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.

The AF ECM will control fuel trim based upon the Bank 2 Sensor 1 signal. If a Bank 2 Sensor 1 DTC sets, the Alternative Fuels ECM will operate in Open Loop fuel control.

A first failure of this DTC will NOT illuminate the MIL and will store as Last Test Failed but not as History.
The AF ECM will illuminate the MIL and store the DTC as History after 2 consecutive drive trips that the diagnostic runs and fails.
The AF ECM will record operating conditions at the time the DTC sets. This information will be stored as Freeze Frame data.