Circuit/System Description
WARNING: This page is about a different car, the 2009 GMC Sierra and 2009 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The accessory power module (APM) monitors its 14-volt circuit when it is enabled for charge or Jump Assist. It requires a minimum voltage on this circuit in order to begin operation. This DTC sets when the 14-volt circuit in the APM is below this minimum level at the time it is enabled. APM functions will run only when an APM enable message from the hybrid powertrain control module (HPCM) is active on the high speed hybrid GMLAN communication circuit.