Circuit/System Description

WARNING: This page is about a different car, the 2019 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.

Vehicles equipped with high voltage storage and propulsion capability are designed with the high voltage circuits isolated from the vehicle chassis. If either the positive or negative high voltage Direct Current (DC) circuits or any of the high voltage Alternating Current (AC) phase circuits lose this isolation to the vehicle chassis, one or more diagnostic trouble codes (DTCs) may set.

The hybrid/EV powertrain control module 2 performs active isolation testing to monitor the internal Hybrid/EV battery pack HV circuits for chassis isolation. The hybrid/EV powertrain control module 2 switches fixed resistors between the high voltage system and vehicle chassis. The difference between the switched-to-chassis state and the unswitched state is used to calculate a resistance-to-chassis value.