Auto Stop/Start System

At the beginning of a drive cycle, when the ignition switch is operated, the auto stop/start system operates the same way as on vehicles without auto stop/start system.

The auto stop/start system is controlled by the Powertrain Control Module (PCM) and the Body Control Module/Gateway Module (BCM/GWM) via FlexRay bus and signals from other system components and modules to determine the correct conditions for system operation. The auto stop/start system detects when it is appropriate to stop and start the engine.

The auto stop/start system automatically stops the engine in appropriate conditions, resulting in zero tailpipe emissions and saving fuel when the vehicle is stationary. When the brake pedal is released, the engine instantly restarts.

The auto stop/start system can be enabled/disabled using the auto stop/start switch in 'Vehicle' menu on the Interactive Control Display Module (ICDM).

Software within the PCM controls the operation of the auto stop/start system. In addition to its own dedicated components the auto stop/start system encompasses many other vehicle systems.

Complex technology interconnects these systems and ensures all the necessary conditions are satisfied by monitoring, among others:

Brake hydraulic system pressure.
Transmission Control Switch (TCS) position.
Road speed.
The state of vital vehicle systems.
Environmental conditions.

The driver will be notified that the engine stops by the auto stop/start warning indicator being illuminated in the Instrument Cluster (IC). Other engine stoppage warnings, for example ignition indicator and low oil pressure indicator will not illuminate during an engine stoppage within an auto stop/start cycle.

The following conditions will prevent an auto stop:

A steering wheel paddle switch has been used to select a gear (transmission Command shift mode).
The ambient air temperature is outside the range of 2°C to 40°C (36°F to 104°F).
The ambient air pressure is below 720 hPa.
The engine coolant temperature is outside the range of 20°C to 107°C (68°F to 224°F).
Brake vacuum is less than the threshold value.
The hood is open.
The driver door is open.
The driver seatbelt is not fastened.
High demand from the climate control system requires the engine to be running, for example windshield demist selected.
The startup battery charge is low.
A Terrain Response (TR) special program is active.
The Hill Descent Control (HDC) is active.
The level in the fuel tank is too low (approximately 6 liters remaining in tank).
Active regeneration of the Diesel Particulate Filter (DPF) is required or in progress.
Auto stop/start system is disabled using the auto stop/start switch.

While the vehicle is stationary, if a condition that prevented an auto stop is removed the PCM automatically performs an auto stop.

The PCM automatically restarts the engine when one of the following occurs:

The brake pedal is released with DRIVE or SPORT selected on the TCS.
The accelerator pedal is pressed.
A paddle switch is used to select a gear.
The REVERSE gear is selected on the TCS.
The climate control system demand increases.
The vehicle speed exceeds approximately 1 km/h (0.5 mph).
The startup battery state of charge is near its lower threshold.
The brake vacuum reduces below the threshold value.
The auto stop/start system is disabled using the auto stop/start switch.

NOTE: When the brake pedal is released during an auto restart the Anti-lock Brake System (ABS) control module applies the brakes to hold the vehicle stationary. The ABS holds the vehicle stationary until the engine restarts.

The following will prevent an auto restart, and require use of the engine stop/start switch to restart the engine:

The hood is open.
The driver seatbelt is not fastened.