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Anti-Theft - Passive Anti-Theft System (PATS)




Anti-Theft

NOTE: The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM).

The Passive Anti-Theft System (PATS) consists of the following components:

- Anti-theft indicator (located in the Instrument Panel Cluster (IPC))

- Encoded ignition Integrated Keyhead Transmitter (IKT) PATS (Passive Anti-Theft System) key(s) (the key contains a transponder and a Remote Keyless Entry (RKE) transmitter)

- PATS (Passive Anti-Theft System) transceiver (located around the ignition lock cylinder and under the lower steering column shroud)

- IPC (Instrument Panel Cluster)

- PCM (located under the battery tray in the engine compartment)

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

The vehicle is equipped with 2 IKT (Integrated Keyhead Transmitter) PATS (Passive Anti-Theft System) keys. The IKTs (Integrated Keyhead Transmitters) operate as a standard PATS (Passive Anti-Theft System) key with an RKE (Remote Keyless Entry) transmitter incorporated into the keyhead. The IKTs (Integrated Keyhead Transmitters) require batteries for the RKE (Remote Keyless Entry) transmitter to operate. A maximum of 4 IKT (Integrated Keyhead Transmitter) keys can be programmed to operate the vehicle. If more than 4 IKT (Integrated Keyhead Transmitter) keys are programmed, the RKE (Remote Keyless Entry) portion of the additional keys do not operate. These additional keys start the vehicle, but do not operate the RKE (Remote Keyless Entry) system. If additional PATS (Passive Anti-Theft System) keys are desired, a standard PATS (Passive Anti-Theft System) key (a non-IKT (Integrated Keyhead Transmitter) key) can be used. For the purposes, the PATS (Passive Anti-Theft System) portion of the IKT (Integrated Keyhead Transmitter) key is referred to as a PATS (Passive Anti-Theft System) key.

Passive Anti-Theft System (PATS) Function

The PATS (Passive Anti-Theft System) function is controlled by the IPC (Instrument Panel Cluster). The PATS (Passive Anti-Theft System) uses the IPC (Instrument Panel Cluster) to carry out all of the PATS (Passive Anti-Theft System) functions such as receiving the identification code from the PATS (Passive Anti-Theft System) 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. Because of the interaction between the IPC (Instrument Panel Cluster) and the PCM, there are parameters that must be set if the IPC (Instrument Panel Cluster) or the PCM (or both) are replaced. Refer to Passive Anti-Theft System (PATS) Parameter Reset . If the IPC (Instrument Panel Cluster) must be replaced for any reason (PATS (Passive Anti-Theft System) concerns or an IPC (Instrument Panel Cluster) concern), the PATS (Passive Anti-Theft System) keys also must be programmed into the new IPC (Instrument Panel Cluster). Refer to Integrated Keyhead Transmitter (IKT) Key Programming Using Diagnostic Equipment . All elements of PATS (Passive Anti-Theft System) must be functional before the vehicle starts. If any of the components are not working correctly, the vehicle does not start.

PATS (Passive Anti-Theft System) is active only for a few seconds when the vehicle is starting. It is not a PATS (Passive Anti-Theft System) concern if the vehicle stalls after it has been running for a minimum of 3 seconds. PATS (Passive Anti-Theft System) cannot disable a running vehicle.

PATS (Passive Anti-Theft System) may cause a vehicle no start due to either the fuel injectors or the starter not operating (starter relay does not close) or both. Always check for PATS (Passive Anti-Theft System) DTCs from the IPC (Instrument Panel Cluster) and DTCs from the PCM when a no-crank or no-start condition exists. A low state of charge in the vehicle battery may cause the PATS (Passive Anti-Theft System) to allow starter operation, but prevent the fuel injectors from operating.

If the anti-theft indicator does not prove out (it may be either flashing or glowing steadily) and one (or both) of the previous conditions (fuel injectors and/or starter inoperative) are present, it may be due to a PATS (Passive Anti-Theft System) concern. If the anti-theft indicator proves out, it may not be a PATS (Passive Anti-Theft System) concern. If the anti-theft indicator does not illuminate at all, it may be an IPC (Instrument Panel Cluster) concern. Refer to the Symptom Chart. Anti-Theft - Passive Anti-Theft System (PATS)

PATS (Passive Anti-Theft System) 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 (Passive Anti-Theft System) -related no-start concerns are investigated.

Unlimited Key Mode

PATS (Passive Anti-Theft System) 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.

If unlimited key mode is enabled, a maximum of 4 IKT (Integrated Keyhead Transmitter) keys can be programmed to the vehicle for RKE (Remote Keyless Entry) functionality. If more keys are required, they should be standard PATS (Passive Anti-Theft System) keys. If more than 4 IKT (Integrated Keyhead Transmitter) keys are programmed to the vehicle, only 4 IKT (Integrated Keyhead Transmitter) keys have RKE (Remote Keyless Entry) functionality, however, all of them start the vehicle, if programmed correctly. Refer to Spare Key Programming - Unlimited Key Mode .

MyKey(R) Feature

The MyKey(R) feature allows a restricted driving mode to be programmed into one (or more) key(s) supplied with the vehicle or into any (PATS (Passive Anti-Theft System)) programmed spare key(s) to promote good driving habits. The MyKey(R) is a restricted key for all consecutive key cycles until the MyKey(R) restricted key is cleared. The remaining key(s) is referred to as an "administrator key" or admin key. There must always be at least one admin key. The IPC (Instrument Panel Cluster) does not allow the last admin key to be programmed into a MyKey(R) restricted key. Both the admin key and the MyKey(R) can be used to see how many admin keys and MyKey(R) restricted keys are programmed to the vehicle, and how many total miles have been driven with the MyKey(R) restricted key active.

When the MyKey(R) feature is programmed, several features are modified including:

Standard Restricted Features

- NOTE: The standard restricted features below cannot be configured in any way.
Belt-Minder(R) chimes periodically with the audio system muted until the driver safety belt is buckled. If Belt-Minder(R) has been disabled when the admin key is in the ignition lock cylinder, Belt-Minder(R) still functions for the MyKey(R) driver. Belt-Minder(R) cannot be disabled by the MyKey(R) driver.


- Audible and visual low fuel warnings are issued when the programmed Distance To Empty (DTE) value is reached (typically 75 miles).

- The parking aid system (if equipped), Blind Spot Information System (BLIS(R)) with cross traffic alert (if equipped) cannot be turned off.

Optional Restricted Features

- NOTE: The optional restricted features below can be configured to the customer preferences.
The volume of the audio system can be programmed to limit the volume to 45% of the maximum volume.


- Vehicle speed can be programmed to be limited to 130 km/h (80 mph). Audible and visual warnings are issued when the vehicle speed of 130 km/h (80 mph) is attained.

- Audible and visual warnings are issued when the preselected vehicle speed of 75, 90 or 105 km/h (45, 55 or 65 mph) is attained.

- The AdvanceTrac(R) always on feature can be configured on or off. If configured to always on, at this time the traction control cannot be disabled by the MyKey(R) driver.

Refer to Information and Message Center in the Description and Operation portion of Instrument Panel, Gauges and Warning Indicators for all of the MyKey(R) system checks and system warning displays.

Refer to MyKey(R) Programming or to the Owner's Literature for MyKey(R) programming information.

Check MyKey(R) System Status

The vehicle system check provides the status of the following MyKey(R) parameters:

- MYKEY DISTANCE- This odometer only tracks mileage when a MyKey(R) is used. If mileage does not accumulate, the intended MyKey(R) is not being used. The only way to reset this odometer to zero is by clearing the MyKey(R). If this odometer is lower than the last time it was checked, the MyKey(R) system has been cleared.

- MYKEY(S) PROGRAMMED- Indicates how many MyKeys(R) are programmed to the vehicle. It can also be used to determine if a MyKey(R) has been cleared.

- ADMIN KEYS PROGRAMMED- Indicates how many admin keys are programmed to the vehicle. It can also be used to determine if an additional spare key has been programmed to the vehicle.

Refer to the Owner's Literature for information on accessing the MyKey(R) system status in the message center.

Using MyKey(R) with Aftermarket Remote Start System

When using an aftermarket remote start system, the default settings recognize the remote start system as an additional admin key. If the remote start system has not been programmed as a MyKey(R) and the driver is a MyKey(R) driver, the driver could drive the vehicle using the remote start system as an admin key with no MyKey(R) restrictions. If requested by the customer to resolve this concern, the aftermarket remote start system needs to be programmed as a MyKey(R). For information on programming the aftermarket remote start system as a MyKey(R), refer to MyKey(R) Programming .