Passive Start

The passive start system relies on the detection of a uniquely coded smart key via Low Frequency (LF) antennas and the Radio Frequency Receiver (RFR) strategically situated within the vehicle. The LF antennas make sure that the smart key is always within the active transmission zone of the antennas wherever the smart key is placed inside the vehicle. For this reason the orientation and positioning of the antennas is critical to the correct functioning of the system.

The smart key also operates the passive entry system.

The passive start system provides a secure interface between the Body Control Module/Gateway Module (BCM/GWM) and the Powertrain Control Module (PCM). This prevents unauthorized starting of the engine. This is achieved by immobilization of the engine crank system and the fuel system using encoded data exchange between the smart key and multiple control modules.

The BCM/GWM communicates with the PCM via the FlexRay connection.

Engine starting is initiated when the encoded data exchange between the smart key and the control modules is verified. The engine management system will then allow engine crank and fueling when an authorization data message is received from the BCM/GWM.

The engine can be started by pressing the ignition switch and depending on the type of transmission:

• The Transmission Control Switch (TCS) is in Park (P) position and the brake pedal is pressed on vehicles with automatic transmission.
• The gear selector is in Neutral (N) position and the clutch pedal is pressed on vehicles with manual transmission.