Code Enable Criteria

WARNING: This page is about a different car, the 2001 GMC Savana, 2001 Chevrolet RV Cutaway, 2001 Chevrolet Cutaway, and 2001 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.

Engine is running.
Engine run time is more than 0.5 second.
Engine speed is more than 300 RPM.
Ignition 1 voltage is more than 8 volts.

DTC sets when MAF sensor frequency signal is more than 13,000 Hertz.