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




Anti-Theft

Principles of Operation

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

Anti-Theft Indicator

NOTE: Replacement of the Passive Anti-Theft System (PATS) transceiver does not require the PATS (Passive Anti-Theft System) keys to be programmed into the Instrument Panel Cluster (IPC) again.

NOTE: Make sure any non-Ford remote start systems have been removed from the vehicle before any PATS (Passive Anti-Theft System) -related no-start concerns are investigated.

NOTE: A minimum of 2 PATS (Passive Anti-Theft System) keys must be programmed into the IPC (Instrument Panel Cluster) before the vehicle starts. They do not need to be Integrated Keyhead Transmitter (IKT) keys. Either 2 IKT (Integrated Keyhead Transmitter) keys, or 2 standard PATS (Passive Anti-Theft System) keys, or a combination of an IKT (Integrated Keyhead Transmitter) key and a standard PATS (Passive Anti-Theft System) key is sufficient for the vehicle to start.

NOTE: If the IPC (Instrument Panel Cluster) and/or the Transmission Control Module (TCM) is being replaced, the parameters must be reset in both modules or the vehicle experiences a PATS (Passive Anti-Theft System) no-start. Refer to Passive Anti-Theft System (PATS) Parameter Reset .

PATS (Passive Anti-Theft System) uses a visual anti-theft indicator located in the IPC (Instrument Panel Cluster). The indicator proves out for 3 seconds when the ignition key is in the ON or START position under normal operation. If there is a PATS (Passive Anti-Theft System) concern, this anti-theft indicator either flashes rapidly or glows steadily when the ignition key is turned to the ON or START position. PATS (Passive Anti-Theft System) also flashes the anti-theft indicator every 2 seconds when the ignition key is in the OFF position to act as a visual theft deterrent. for the anti-theft indicator.

Encoded Passive Anti-Theft System (PATS) Keys

PATS (Passive Anti-Theft System) uses a special ignition key, called an IKT (Integrated Keyhead Transmitter) key that is larger than a conventional ignition key. It contains a permanently installed electronic device called a transponder and also has the Remote Keyless Entry (RKE) transmitter integrated into the keyhead. Each transponder contains a unique encrypted identification code which is one of a very large number of combinations. The addition of this transponder to the key makes it an "encoded" key. The PATS (Passive Anti-Theft System) portion of the IKT (Integrated Keyhead Transmitter) key does not require batteries and should last the lifetime of the vehicle. The transmitter portion of the IKT (Integrated Keyhead Transmitter) key has a battery. Each PATS (Passive Anti-Theft System) key must be programmed into the IPC (Instrument Panel Cluster) before it can be used to start the vehicle. A maximum of 4 IKT (Integrated Keyhead Transmitter) keys can be programmed to start the vehicle and also operate the RKE (Remote Keyless Entry) functions. If more than 4 IKT (Integrated Keyhead Transmitter) keys are programmed, the RKE (Remote Keyless Entry) portion of the additional IKT (Integrated Keyhead Transmitter) keys do not operate and the SJB (Smart Junction Box) sets DTC B1138, and the IPC (Instrument Panel Cluster) sets DTC B109E:42 (both DTCs indicate a memory full condition). These additional keys start the vehicle, but cannot operate the RKE (Remote Keyless Entry) system, as only the first 4 IKT (Integrated Keyhead Transmitter) keys programmed have that RKE (Remote Keyless Entry) functionality. 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. There are specific general procedures described that must be carried out if a new PATS (Passive Anti-Theft System) key is necessary. Refer to Integrated Keyhead Transmitter (IKT) Key Programming Using Diagnostic Equipment or Key Programming Using Two Programmed Keys .

Passive Anti-Theft System (PATS) Transceiver

The PATS (Passive Anti-Theft System) transceiver is located under the steering column shroud and communicates with the encoded ignition key. During each vehicle start sequence, the PATS (Passive Anti-Theft System) transceiver reads the encoded ignition key ID code and sends data to the IPC (Instrument Panel Cluster). The IPC (Instrument Panel Cluster) validates the code, and if it is the correct code, sends a message to the TCM (Transmission Control Module) to enable the engine and the electric drive.

Passive Anti-Theft System (PATS) Operation

The PATS (Passive Anti-Theft System) function is controlled by the IPC (Instrument Panel Cluster). With this type of PATS (Passive Anti-Theft System) , there are parameters that need to be reset if either the IPC (Instrument Panel Cluster) and/or the TCM (Transmission Control Module) are replaced. Refer to Passive Anti-Theft System (PATS) Parameter Reset . When the PATS (Passive Anti-Theft System) key is turned to the ON or START position, the IPC (Instrument Panel Cluster) initiates the key interrogation sequence by sending a voltage signal to the PATS (Passive Anti-Theft System) transceiver. The transceiver then uses its antenna to bounce a signal off the transponder in the PATS (Passive Anti-Theft System) key. This process "reads" the PATS (Passive Anti-Theft System) key ID code and sends the key ID code back to the IPC (Instrument Panel Cluster) , which interprets it and determines if it matches one of the stored key codes. If it does match one of the stored key codes, the IPC (Instrument Panel Cluster) sends a message to the TCM (Transmission Control Module) to enable the engine and the electric drive. If it does not match one of the stored key codes, or it is only a partial key read or no key read, the IPC (Instrument Panel Cluster) sends a message to the TCM (Transmission Control Module) to not enable the engine and the electric drive. The anti-theft indicator in the IPC (Instrument Panel Cluster) flashes (or glows steadily) and the IPC (Instrument Panel Cluster) stores one or more DTCs. 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 cannot start. If the IPC (Instrument Panel Cluster) must be replaced for any reason, the PATS (Passive Anti-Theft System) keys must also be programmed into the new IPC (Instrument Panel Cluster). Refer to Integrated Keyhead Transmitter (IKT) Key Programming Using Diagnostic Equipment .

PATS (Passive Anti-Theft System) disables the vehicle from starting if there is:

- a damaged PATS (Passive Anti-Theft System) key.

- a non-programmed PATS (Passive Anti-Theft System) key.

- a non-PATS (Passive Anti-Theft System) key (key has no electronics).

- less than 2 keys programmed.

- damaged wiring.

- a damaged transceiver.

- a damaged IPC (Instrument Panel Cluster).

- a damaged TCM (Transmission Control Module).

Passive Anti-Theft System (PATS) PIDs

Monitoring the PATS (Passive Anti-Theft System) PIDs can be very useful in determining which diagnostic steps to follow. Viewing the MASTERKEY (master key) PID with both keys determines if the key is a programmed key and can also be used to prove out the transceiver, circuitry and the IPC (Instrument Panel Cluster). A master key is a key that is programmed into the IPC (Instrument Panel Cluster). Viewing the MIN_KEYS (minimum number of keys) PID (this PID does not change) determines the minimum number of keys that must be programmed into the IPC (Instrument Panel Cluster). There must be at least 2 keys programmed into the IPC (Instrument Panel Cluster) in this type of PATS (Passive Anti-Theft System) before the vehicle starts. Viewing the N_KEYCODE (number of keys programmed) PID determines if the minimum number of keys have been programmed into the IPC (Instrument Panel Cluster). If the N_KEYCODE PID reads 0 or 1, additional key(s) need to be programmed into the IPC (Instrument Panel Cluster) in order to meet the minimum of 2 keys. If the N_KEYCODE PID reads 0 or 1, and the MASTERKEY PID reads Not Present, that particular key must be programmed into the IPC (Instrument Panel Cluster). If the N_KEYCODE PID reads 1, and the MASTERKEY PID reads Present, that particular key is already programmed into the IPC (Instrument Panel Cluster). In this particular case, there are not enough keys programmed (a minimum of 2 are needed before the vehicle starts) into the IPC (Instrument Panel Cluster) and at least 1 more key needs to be programmed before the vehicle starts. Refer to Integrated Keyhead Transmitter (IKT) Key Programming Using Diagnostic Equipment .

Also, if the unlimited key mode has been enabled, the N_KEYCODE PID always reads 2, after the first 2 keys are programmed into the IPC (Instrument Panel Cluster) , regardless of how many additional keys are added.

When the parameters are reset, it clears (erases) the TCM (Transmission Control Module) ID from the IPC (Instrument Panel Cluster). A parameter reset causes the TCM (Transmission Control Module) to send a TCM (Transmission Control Module) ID to the IPC (Instrument Panel Cluster) that is necessary for the system to operate. Make sure to cycle the key at least once, then turn the key ON and make an attempt to start the vehicle for 3-5 seconds before attempting more procedures. If only a TCM (Transmission Control Module) parameter reset occurs, the ID stored in the IPC (Instrument Panel Cluster) does not match the ID being sent by the TCM (Transmission Control Module) , and can cause a PATS (Passive Anti-Theft System) -related no-start. Carry out a PATS (Passive Anti-Theft System) parameter reset, then turn the key ON and make an attempt to start the vehicle for 3-5 seconds before attempting more procedures.

If the PCM_ID (TCM (Transmission Control Module) id status) PID reads Stored, the IPC (Instrument Panel Cluster) has a TCM (Transmission Control Module) ID stored. If it reads Not Stored, a parameter reset may resolve this concern. If the PATSENABL (vehicle enable status) PID reads Disabled, and the N_KEYCODE PID reads 2 or more and the MASTERKEY PID reads Present, the IPC (Instrument Panel Cluster) and the TCM (Transmission Control Module) need to have their parameters reset. Refer to Passive Anti-Theft System (PATS) Parameter Reset .

If the PATSENABL PID reads Disabled, and the N_KEYCODE PID reads 1 and the MASTERKEY PID reads Present, or if the N_KEYCODE PID reads 0 and the MASTERKEY PID reads Not Present, a minimum of 2 keys need to be programmed into the IPC (Instrument Panel Cluster). Refer to Integrated Keyhead Transmitter (IKT) Key Programming Using Diagnostic Equipment .

If the MASTERKEY PID continues to read Not Present after programming, this may indicate a defective key. The SPAREKEY PID is defaulted to ENABLE. With the SPAREKEY PID displaying ENABLE, the IPC (Instrument Panel Cluster) accepts more than 2 keys (up to a maximum of 8) being programmed into the IPC (Instrument Panel Cluster) using Key Programming Using Two Programmed Keys . It can be toggled to DISABLE if the customer wants to disable the customer spare key programming function. Refer to Key Programming Switch State Control . This switch state control does not affect the Integrated Keyhead Transmitter (IKT) Key Programming Using Diagnostic Equipment procedure.

In summary, in order for the vehicle to start, the PATS (Passive Anti-Theft System) PIDs and their correct state they must be in are as following:





Use of Standard Passive Anti-Theft System (PATS) Keys

When using a standard (non-IKT (Integrated Keyhead Transmitter)) PATS (Passive Anti-Theft System) key to start the vehicle, an IKT (Integrated Keyhead Transmitter) key (from another vehicle) on the same key ring can possibly be programmed into the vehicle for remote entry functionality, resulting in the IKT (Integrated Keyhead Transmitter) key being able to operate the lock and unlock functions of the vehicle (but the IKT (Integrated Keyhead Transmitter) key cannot start the vehicle). This should not cause a PATS (Passive Anti-Theft System) no-start of either the first or the second vehicle, but the IKT (Integrated Keyhead Transmitter) key may be able to operate the lock and unlock functions of both vehicles. The IKT (Integrated Keyhead Transmitter) key is able to start the original vehicle to which it is programmed and is not able to start the second vehicle. At this time, it is necessary to carry out an Integrated Keyhead Transmitter (IKT) Key Programming Using Diagnostic Equipment procedure and then to make certain the IKT (Integrated Keyhead Transmitter) key for the second vehicle is removed from the key ring in order to prevent this concern from occurring again. Also, if an IKT (Integrated Keyhead Transmitter) key is used to start the vehicle, the vehicle only reads the IKT (Integrated Keyhead Transmitter) key in the ignition lock cylinder and cannot read the second IKT (Integrated Keyhead Transmitter) on the key ring. Using an IKT (Integrated Keyhead Transmitter) key to start both vehicles, rather than standard PATS (Passive Anti-Theft System) keys, prevents the second IKT (Integrated Keyhead Transmitter) (transmitter portion only) from being programmed into the first vehicle.

Unlimited Key Mode

PATS (Passive Anti-Theft System) contains a feature called unlimited key mode and uses the UNL_KEY_MODE PID. This feature allows a customer to program more than 8 keys to their vehicle if they request it. 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, but no other keys from outside can be used to operate the vehicles. 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 .
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