Circuit/System Verification
WARNING: This page is about a different car, the 2012 GMC Yukon, 2012 Chevrolet Tahoe, and 2012 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
Ignition ON, observe the scan tool Hybrid Battery 1-20 parameters. Each reading should be between 10-19 V, and all readings should be within 1.5 V of each other.