Circuit/System Description

Devices connected to the powertrain high speed GMLAN serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the devices. The devices have prerecorded information about what messages are needed to be exchanged on the serial data circuits, for each virtual network. The messages are supervised and also, some periodic messages are used by the receiver device as an availability indication of the transmitter device. Each message contains the identification number of the transmitter device.

The motor control module and the hybrid powertrain control module are all internal to the starter/generator control module. All circuits to the hybrid powertrain control module are also internal to the starter/generator control module.

Communication diagnostics for the serial data, including device power and ground as well as the wakeup circuits for the motor control module and the hybrid powertrain control module are all diagnosed from external sources only to the starter/generator control module connector because any circuit fault condition within the starter/generator control module will cause a complete replacement.