Antitheft and Alarm Systems: Description and Operation

Anti-Theft

NOTE: The Passive Anti-Theft System (PATS) is available on this vehicle as an option. The vehicle must be ordered with or without PATS by the customer. It is not a dealer-installed option.

PATS vehicles consist of the following components:

- Anti-theft indicator (located in the Instrument Panel Cluster (IPC))
- Encoded ignition key(s) (the key contains a transponder)
- PATS transceiver
- IPC
- PCM

Non-PATS vehicles consist of the following components:

- Anti-theft indicator (located in the IPC)
- Non-PATS ignition key(s) (conventional ignition key)
- IPC
- PCM

PATS uses radio frequency identification technology to deter a drive-away theft. Passive means that it does not require any activity by the user.

Passive Anti-Theft System (PATS) Function

The PATS function is controlled by the IPC. The PATS uses the IPC to carry out all of the PATS functions such as receiving the identification code from the PATS key, issuing a signal to the PCM to control the starter and fuel injectors enable, and initiating the key interrogation sequence when the ignition key is turned to the ON or START position. All elements of PATS must be functional before the vehicle starts. If any of the components are not working correctly, the vehicle cannot start.

PATS may cause a vehicle no start due to either the fuel injectors or the starter not operating, or both.

PATS is active only for a few seconds when the vehicle is starting. It is not a PATS concern if the vehicle stalls after it has been running for a minimum of 3 seconds. PATS does not disable a running vehicle.

Factory Invoiced Accessory (FIA)

Vehicles may be equipped with a remote start system that is a dealer-installed Factory Invoiced Accessory (FIA). The remote start fob for this system uses a small device that is about half the size of a conventional RKE fob, but only has one button on it. If the remote start system is installed on the vehicle and the unlimited mode is not enabled, PATS allows up to 7 PATS keys to be programmed into the IPC. The remote start system uses up one of the 8 total PATS keys that can be programmed into the IPC. The number of keys that are programmed into the PATS can be determined by viewing the IPC PID N_KEYCODE.

PATS is not compatible with aftermarket remote start systems, which allow the vehicle to be started from the exterior of the vehicle. These systems may reduce the security of the vehicle, and also may be the cause of no-start concerns. Remote start systems must be removed from the vehicle before any PATS-related no-start concerns are investigated.

Anti-Theft Indicator Operation

With Passive Anti-Theft System (PATS)

With the key in the OFF position, the anti-theft indicator flashes every 2 seconds for 10 seconds and then it goes out and stays off. With the key in the ON position, the anti-theft indicator proves-out for 3 seconds, then goes out to indicate the PATS is functional and the vehicle has been enabled.

Without Passive Anti-Theft System (PATS)

With the key in the OFF position, the anti-theft indicator does not flash. With the key in the ON position, the anti-theft indicator proves-out for 3 seconds, then goes out to indicate the vehicle has been enabled.

Unlimited Key Mode

PATS contains a feature called unlimited key mode. This feature allows a customer to program more than 8 vehicle keys, if requested. Each vehicle in unlimited key mode is set up with a special unlimited transponder security key code. This allows all the customer vehicles to share the same mechanically cut keys. For an individual customer, any randomly selected security key that has been previously mechanically cut and electronically programmed to the vehicle is acceptable. Refer to Spare Key Programming - Unlimited Key Mode Unlimited Key Mode.