Diagnostic Aids

WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

This DTC indicates that the cause of a discharged battery is likely a parasitic current draw, rather than a defective battery.
If the vehicle is equipped with an auxiliary battery (TP2), verify that there is not a fuse installed in the STUD 1 Fuse 70 position of the underhood fuse block. A plastic plug may be installed in this position instead of a fuse. If a fuse is installed in this position and any optional equipment is powered by the auxiliary battery, it will discharge the primary battery in addition to the auxiliary battery.
Verify that all accessories are turned OFF, including optional accessories that the vehicle may have been wired for, but does not have installed, such as auxiliary lights. If an optional accessory swich is left in the ON position, it may energize a relay that will discharge the battery over time, even if the accessory is not installed on the vehicle.
A battery discharging for no apparent reason while the vehicle is parked can be caused by an intermittent draw, such as a module waking up, or a continuous draw, such as a dome light or stuck relay. Look and listen for any components that may be operating when they should turn off, such as a fuel pump.