Autostop Criteria

The ECM will send an Autostop state message to the body control module (BCM) and shut down the engine when all of the following criteria is met. The BCM will transmit the Autostop state message to the instrument cluster where the tachometer needle will point at the Autostop (500 RPM point) indicating the engine has been shut down by the Stop/Start System.

• Initial minimum vehicle speed during drive cycle must be 19 km/h (12 MPH) or greater. Subsequent autostop minimum speed may vary from 2-10 km/h (1-6 MPH), depending on vehicle
• Ambient and engine coolant temperature correlation meets specified values.
• Ambient and transmission fluid temperature correlation meets specified values.
• Hood switch status is closed
• Brake booster vacuum is greater than 45 kPa (7 PSI)
• Transmission gear selector is in the Drive position
• Vehicle speed is less than 5 km/h (3 MPH)
• Engine speed is below 1 500 RPM
• Engine coolant temperature is less than 120°C (248°F)
• Ambient temperature is greater than -10°C (14°F)
• No A/C compressor request from HVAC (A/C or Defrost modes)
• Battery voltage greater than 12 V
• Battery state of charge greater than 75% (changes with state of health)