Circuit/System Description

Control modules connected to the high and low speed GMLAN serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the control modules. The control modules 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 module as an availability indication of the transmitter module. Each message contains the identification number of the transmitter module.

The serial data gateway module (SDGM) energizes the wake up signal to activate the accessory DC power control module (APM) and another wake up signal to activate the hybrid powertrain control module (HPCM) which is inside the drive motor generator power inverter module (PIM) when communication is needed. The HPCM reports all DTCs for the APM.