Powertrain Control Module (Pcm)

The SAM system is implemented by the PCM, which is the smart generators LIN master. An example of PCM strategy implementation would be during the cranking phase to engine running state. When the driver changes the ignition to cranking mode, there are two sub phases of the SAM strategy implemented by the PCM:

• During the first phase the voltage set point will be set at low value, to reduce the torque and help the engine to start.
• In the second phase, after a specific Revolutions Per Minute (RPM) threshold the voltage set point must be set at a high value to reduce the RPM overshoot.

Once the engine has started, a "system running" SAM strategy is applied to the smart generator and remains until the engine is stopped. While the system is in the "system running" state, the BCM and PCM monitor certain conditions to determine voltage minimum output and the voltage maximum output to be used in the SAM strategies. The following are some of the inputs used:

• The battery current from the BCM
• The battery temperature (°C) from the BCM
• The battery voltage (V) from the BCM
• The battery SOC (%) from the BCM
• The maximum voltage allowed by the BCM (V)
• The minimum voltage allowed by the BCM (V)
• The IBS status signals from the BCM
• The SAM failure status from the BCM
• Cooling fan at max speed (if equipped with dual speed fan)
• Regeneration active (diesel engines only)
• Variable Valve Actuation (VVA) state (late opening mode or multi lift active)
• MultiAir: Oil temperature limitation in cold condition
• PWM cooling fan actual speed (if equipped with a PWM fan)
• Low speed coolant radiator PWM pump
• Low pressure fuel PWM pump
• Actual engine speed and engine load
• ESS availability (for export ESS equipped vehicles only)

Driving condition detection is used by the SAM system to recognize if the vehicle is in one of three states:

• Passive Boost (drive condition 1)
• Steady State (drive condition 2)
• Regenerative Braking (drive condition 3)

This driving condition information is used to determine if the driveline is closed or if the driveline is open.

Driveline closed means:

• Manual Transmission (MTX): Gear engaged and clutch position is high. This gear engaged information is determined by using internal module variables while the clutch position switch determines the position of the clutch pedal.
• Automatic Transmission (ATX): Neutral or drive clutch engaged. This information is determined by using CAN signals received from the Transmission Control Module (TCM).

Driveline open means:

• MTX Gear neutral or clutch position is not high
• ATX Neutral or gear engaged

When an engine fault or its sensors or actuators do not permit drive condition recognition, the system defaults into the steady state drive condition 2.

The SAM strategy is assigned a value ranging 0-10. Each number value indicates a SAM strategy that the PCM specifically identifies and broadcasts on the CAN-C network data bus.

Charging system failures are managed by the PCM and this information is bussed over the CAN-C data network to the IPC for display. The smart generator is controlled by a EVR routine in the PCM. The EVR algorithm is able to recognize fault conditions and sends fault indication signals over the CAN-C data network.

By means of its own regulation system, the smart generator is able to recognize its own fault conditions and indicate them by setting specific LIN signals. The fault conditions that are managed depends on the regulator type and are as follows:

• Generator Fault Communication Error
• Generator Electrical Fault
• Generator Over Temperature Fault
• Generator Mechanical Fault
• Generator Communication Time Out Fault

Each of these faults are communicated by the PCM setting the appropriate DTC as well as broadcasting the proper fault indication signals over the CAN-C data network.