Passive Anti-Theft System (PATS): Notes

The PATS function is controlled by the RFA module, the BCM and the PCM.

When the START/STOP button is pressed, the RFA module initiates the key initialization sequence by activating the 3 interior PATS antennas. Each PATS antenna transmits a low frequency signal approximately 1 m (3 ft) radius of each antenna. If a passive key is within range of an interior PATS antenna, the passive key activates.

When the passive key activates, it sends the PATS identification code to the Radio Frequency (RF) receiver via a high frequency signal. The Radio Frequency (RF) receiver interprets the high frequency signal from the passive key and sends the information to the RFA module over a LIN-based circuit. If the RFA module detects a programmed passive key is inside the vehicle, it communicates this information to the BCM and the ignition transitions out of OFF.

When the ignition transitions out of OFF and the modules initialize, the RFA module, the BCM and the PCM exchange their identifications. If each of the modules receive the correct identification from each other, the PATS disables and allows the vehicle to start. If the PATS prevents the vehicle from starting, a DTC is stored in one of the 3 modules.

The PATS and the RKE system share the operation of several components including the passive key and the Radio Frequency (RF) receiver. If there is a concern with either of these components, the PATS and the RKE system are both affected.

The vehicle can experience a PATS no-start if a failure occurs with:

• any PATS antenna.
• the battery in the passive key
• the Radio Frequency (RF) receiver

However, in the event of one of these failures, place a valid programmed passive key in the backup location to allow the vehicle to start. The PATS front antenna activates the passive key when the START/STOP button is pressed.

The RFA module and the BCM control the ignition modes and, in conjunction with the PCM, control the PATS.