Diagnostic Aids
WARNING: This page is about a different car, the 2006 Pontiac Montana SV6, 2006 Chevrolet Uplander, and 2006 Buick Terraza. However, it is still accessible from the selected car via links, so may be relevant.
The most likely reasons for DTC B1001 being set are incorrect calibration files were downloaded to the module or the module was replaced without the recalibration having been performed.