Circuit/System Description

The starter/generator control module (SGCM) monitors to determine performance of the motor generator unit (MGU).

The AutoStop ready indication will be a DIC message that indicates the following two states:

• AUTOSTOP AVAL (AutoStop Available)
• AUTOSTOP UNAVAIL (AutoStop Unavailable)

The engine control module (ECM) will send an AutoStop state message to the body control module (BCM). The BCM will transmit the AutoStop state message to the instrument panel cluster (IPC). If all of the following conditions are true the indicated state will be Avail, otherwise the state will be Unavail:

• Vehicle speed of 4 mph exceeded (initially)
• Ambient temperature above -15°C (5°F)
• Hybrid and powertrain components temperatures in hybrid operational ranges
  • Hybrid battery temperature is greater than 10°C (50°F) (approximate) and less than 50°C (122°F).
  • Transmission fluid temperature is greater than 35°C (95°F) (ambient temperature less than 10°C (50°F).
  • Transmission fluid temperature is greater than 20°C (68°F) (ambient temperature greater than 10°C ( 50°F).
  • Transmission fluid temperature is less than 110°C (230°F).
  • Engine coolant temperature is greater than 80°C (176°F) (ambient temperature less than 10°C ( 50°F).
  • Engine coolant temperature is greater than 47°C (176°F) (ambient temperature greater than 10°C ( 50°F)
  • Engine coolant is less than 121°C (250°F)
• Vehicle in Drive (No autostops in I, L or Reverse)
• HVAC compressor system request Engine ON = False
• Grade less than 18 percent
• Sufficient brake vacuum
• SOC is greater than required for AutoStop (70 percent).
• Battery discharge power capability is greater than minimum required for AutoStart (6200 watts).
• Acceptable 12 volt battery status (voltage, current, temperature)
• No wheel slip (ABS or Traction Control) active
• EVPR not running small leak test
• Hood is closed.
• Default action 1, 2, 3, or 4 not active