Ignition OFF When Disconnecting Battery Notice
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2006 GMC Savana Special, 2006 GMC Savana Camper Special, 2006 GMC Savana, 2006 Chevrolet RV Cutaway, and 2006 Chevrolet Cutaway. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Always turn the ignition OFF when connecting or disconnecting battery cables, battery chargers, or jumper cables. Failing to do so may damage the Powertrain Control Module (PCM) or other electronic components.