Hybrid Powertrain Control Module
Location
The hybrid powertrain control module is a non-serviceable, flash-programmable micro-processor that is part of the generator control module.
Operating Functions
The hybrid powertrain control module is the main controller of powertrain operation. The hybrid powertrain control module determines when to perform normal operating modes such as auto stop, launch assist mode, and regenerative braking. The hybrid powertrain control module also operates in conjunction with the battery energy control module to determine when to enable and disable the DC high voltage circuits. The motor control module operates the drive motor based upon hybrid powertrain control module commands.
Communication and Hosted Diagnostics
The hybrid powertrain control module is the host controller for DTC and scan tool parameter information for the following control modules:
- 14V power module
- Drive motor control module
- Battery energy control module
These modules diagnose their own operation and determine when a fault condition is present. The 14V power module communicates diagnostic status to the hybrid powertrain control module over serial data.
The drive motor control module and the hybrid powertrain control module exchange information and commands on a serial peripheral interface bus internal communication circuit as well as the hi-speed serial data communication circuit.
In the event the battery energy control module (BECM) communicates a fault condition, the hybrid powertrain control module will determine if one or more operating modes are affected and notify the vehicle operator by requesting the MIL illuminate and/or by displaying a message in the Driver Information Center. In addition, the hybrid powertrain control module will store the associated DTC information for retrieval by a scan tool. Some hosted modules may require an ignition cycle to clear certain DTCs from the hybrid powertrain control module.
Circuit Inputs
In addition to data parameters, the hybrid powertrain control module directly monitors the following signal circuits:
- Engine crankshaft position sensor signal (via serial data message from ECM - not direct)
- High voltage interlock circuit
- Brake Pedal Position
- Drive Motor Temperature (via motor control module)
- Drive Motor Position (via motor control module)
- Hood switch
- Various internal signals (temps, etc.)
Circuit Outputs
In addition to control through other controllers, the hybrid powertrain control module directly controls:
- Cooling Fan
- Auxiliary Transmission fluid pump
- Drive Motor
- Drive Motor Cooling pump