Circuit/System Description

WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

The high voltage interlock circuit (HVIC) is utilized to verify high voltage component integrity. HVIC is a circuit loop that passes through certain high voltage components. HVIC is used to determine if access to high voltage components is being attempted. The opening of these high voltage components causes HVIC to open. The battery energy control module (BECM) sources about 12 mA of current on the 5V HVIC loop. The BECM monitors both the HVIC source circuit current and the HVIC return circuit current in order to detect circuit faults. Both motor control modules (MCMs) monitor the circuit for current in order to detect an open condition. When the BECM and/or the MCMs sense conditions such as a loss of HVIC current, the high voltage contactor relays are commanded open by the hybrid powertrain control module (HPCM).