Operation CHARM: Car repair manuals for everyone.
Home >> Ford Truck >> 2012 >> Edge AWD V6-3.7L >> Repair and Diagnosis >> Accessories and Optional Equipment >> Antitheft and Alarm Systems >> Testing and Inspection >> Initial Inspection and Diagnostic Overview >> Principles Of Operation >> Anti-Theft - Passive Anti-Theft System (PATS) >> With Intelligent Access (IA)

With Intelligent Access (IA)




Anti-Theft - With Intelligent Access (IA)

Principles of Operation

Push Button Start Components

Passive Start Antennas

There are three passive start antennas. The passive start antennas are hardwired to the Remote Function Actuator (RFA) module and when activated by the RFA (Remote Function Actuator) module, they transmit a low frequency signal that activates an Intelligent Access (IA) key.

Backup Transceiver

The backup transceiver is used as a backup device. If the vehicle fails to start conventionally, an IA (Intelligent Access) key can be placed in the backup slot to allow the vehicle to start. The backup transceiver is located next to the slot and activates any IA (Intelligent Access) key that is placed in the slot. The transceiver is wired to the RFA (Remote Function Actuator) module and when activated it sends out a signal to activate an IA (Intelligent Access) key. Once the key is activated, it sends a signal back to the transceiver which is then sent to the RFA (Remote Function Actuator) module.

Tire Pressure Monitor (TPM) Module

The Tire Pressure Monitor (TPM) module has a dedicated power and ground. It communicates all IA (Intelligent Access) and Remote Keyless Entry (RKE) information to the RFA (Remote Function Actuator) module through a dedicated single circuit network. The TPM (Tire Pressure Monitor) module is a receiving antenna that receives the high frequency signals from an IA (Intelligent Access) key. It also receives the signals from an RKE (Remote Keyless Entry) command.

IA (Intelligent Access) Key

The IA (Intelligent Access) receives the low frequency signals from the passive start antennas. When the IA (Intelligent Access) key is activated by one of the low frequency signals, it sends out a high frequency signal that is received by the TPM (Tire Pressure Monitor) module. The IA (Intelligent Access) key also contains a key blade that is used to enter the vehicle as a backup.

Start/Stop Switch

The start/stop switch is a momentary contact switch that is hardwired to the RFA (Remote Function Actuator) module, Body Control Module (BCM), and the PCM. When the switch is pressed, it signals the RFA (Remote Function Actuator) module, BCM (Body Control Module), and the PCM that there is a request to either switch the ignition on or start the engine. The start/stop switch is connected to both modules as a backup in case of a failure. If there is a circuit failure to either module from the start/stop switch, the modules communicate the start/stop switch request to each other over the Medium Speed Controller Area Network (MS-CAN).

Push Button Start Operation





NOTE: The IA (Intelligent Access) feature is a programmable parameter and can be enabled/disabled with a scan tool. If the feature is disabled, the Intelligent Access (IA) feature to enter the vehicle and passive starting will be inoperative. To start the vehicle, the IA (Intelligent Access) key has to be placed in the backup slot. for information on enabling/disabling the IA (Intelligent Access) feature.

The Passive Anti-Theft System (PATS) function is controlled by the RFA (Remote Function Actuator) module, BCM (Body Control Module), and PCM.

When the start/stop switch is pressed, the RFA (Remote Function Actuator) module initiates the key initialization sequence by activating the 3 interior IA (Intelligent Access) passive start antennas. Each passive start antenna transmits a low frequency signal approximately 1 m (3 ft) radius of each antenna. If an IA (Intelligent Access) key is within range of 1 of the 3 interior passive start antennas, the IA (Intelligent Access) key is activated. Once the IA (Intelligent Access) key is activated, it sends the PATS (Passive Anti-Theft System) identification code to the TPM (Tire Pressure Monitor) module via a high frequency signal. The TPM (Tire Pressure Monitor) module interprets the high frequency signal from the IA (Intelligent Access) key and sends the information to the RFA (Remote Function Actuator) module over a dedicated network. If the RFA (Remote Function Actuator) module determines that a programmed IA (Intelligent Access) key is inside the vehicle, it communicates with the BCM (Body Control Module) over the MS-CAN (Medium Speed Controller Area Network) and allows the ignition to be transitioned out of off. When the ignition is turned on and the modules initialize, the RFA (Remote Function Actuator) module, BCM (Body Control Module), and the PCM exchange their IDs over the MS-CAN (Medium Speed Controller Area Network) and High Speed Controller Area Network (HS-CAN). If each of the modules receive the correct ID from each other, PATS (Passive Anti-Theft System) is enabled and allows the engine to start. If PATS (Passive Anti-Theft System) disables the engine from starting, STARTING SYSTEM FAULT is displayed in the message center and a DTC is stored in one of the 3 modules.

PATS (Passive Anti-Theft System) and the RKE (Remote Keyless Entry) system share the operation of several components including the IA (Intelligent Access) key and the TPM (Tire Pressure Monitor) module. If there is a concern with either of these components, both PATS (Passive Anti-Theft System) and the RKE (Remote Keyless Entry) system are affected. Refer to Doors, Hood and Trunk &/or Locks for information on the RKE (Remote Keyless Entry) and IA (Intelligent Access) features.

The RFA (Remote Function Actuator) module in conjunction with the BCM (Body Control Module) controls the ignition modes and in conjunction with the PCM controls the starting system. If there is a concern with the starting system or the ignition modes, and PATS (Passive Anti-Theft System) has been eliminated as the cause, refer to Starting System for a starting system concern or Steering Column for the ignition modes.

Backup Starting

The vehicle can experience a PATS (Passive Anti-Theft System) no start if there is a failure of any passive start antenna, the battery in the IA (Intelligent Access) key, or the TPM (Tire Pressure Monitor) module. However, in the event of one of these failures, the IA (Intelligent Access) key can be placed in the backup slot to allow the vehicle to start. If a programmed IA (Intelligent Access) key is in the backup slot when the backup transceiver is activated, it activates the IA (Intelligent Access) key and the identification code is sent back to the RFA (Remote Function Actuator) module.

Interior Passive Start Antenna Ranges

NOTE: Some brands/types of mobile phone or laptop computer chargers may cause interference that could lead to a PATS (Passive Anti-Theft System) no-start if the IA (Intelligent Access) key is within a few inches of the charger and the NO KEY DETECTED message is displayed in the message center. If a concern is observed, move the IA (Intelligent Access) key away from the charger and attempt to start the vehicle.

There are 3 passive start antennas that are used solely for the purpose of starting the vehicle. They are located in the front of the floor console, in the rear of the floor console, and and under the liftgate scuff trim panel below the liftgate striker. When activated, each antenna sends out a low frequency signal with an approximate range of 1 m (3 ft). A programmed IA (Intelligent Access) key must be in range of 1 of the 3 antennas for PATS (Passive Anti-Theft System) to operate.

If an IA (Intelligent Access) key is placed in the far outside edges of the interior, like above a sun visor or in a door map pocket, the vehicle might experience a no-start. If the IA (Intelligent Access) key is located in one of these areas and there is a no-start condition, move the IA (Intelligent Access) key out of the area and attempt to start the vehicle. If the key is outside the range of a passive start antenna, NO KEY DETECTED is displayed in the message center.

No Key Detected Message

The NO KEY DETECTED message can be displayed in the message center in either of the following scenarios.

When the ignition is off and the start/stop switch is pressed and a programmed IA (Intelligent Access) key is not detected inside the vehicle.

When the engine has been started or the ignition is in the RUN mode and an IA (Intelligent Access) key is no longer detected inside the vehicle. The RFA (Remote Function Actuator) module activates all passive start antennas to search the inside of the vehicle for an IA (Intelligent Access) key any time a door or liftgate is opened and then closed or the vehicle is in motion. This strategy prevents the IA (Intelligent Access) key from being separated from an already running vehicle. If an IA (Intelligent Access) key is no longer in the vehicle, the ignition remains in RUN and the engine continues to run. If the start/stop switch is pressed to turn the ignition off, the engine can be restarted without an IA (Intelligent Access) key present inside the vehicle for approximately 20 seconds, during that time RESTART NOW OR KEY IS NEEDED is displayed in the message center. After 20 seconds an IA (Intelligent Access) key has to be present to start the engine or transition the ignition out of off.

Passive Anti-Theft System (PATS) PIDs

The Passive Anti-Theft System (PATS) PIDs are a useful tool when diagnosing a PATS (Passive Anti-Theft System) concern. They can also be used to determine if unlimited key mode or customer spare key programming are enabled/disabled.





Field-Effect Transistor (FET) Protection

Field-Effect Transistor (FET) is a type of transistor that, when used with module software, monitors and controls current flow on module outputs. The FET (Field-Effect Transistor) protection strategy prevents module damage in the event of excessive current flow.

The RFA (Remote Function Actuator) module utilizes a FET (Field-Effect Transistor) protective circuit strategy for many of its outputs (for example, a headlamp output circuit). Output loads (current level) are monitored for excessive current (typically short circuits) and are shut down (turns off the voltage or ground provided by the module) when a fault event is detected. A continuous DTC is stored at the fault event and a cumulative counter is started.

When the demand for the output is no longer present, the module resets the FET (Field-Effect Transistor) circuit protection to allow the circuit to function. The next time the driver requests a circuit to activate that has been shut down by a previous short (FET (Field-Effect Transistor) protection) and the circuit remains shorted, the FET (Field-Effect Transistor) protection shuts off the circuit again and the cumulative counter advances.

When the excessive circuit load occurs often enough, the module shuts down the output until a repair procedure is carried out. Each FET (Field-Effect Transistor) protected circuit has 3 predefined levels of short circuit tolerance based on the harmful effect of each circuit fault on the FET (Field-Effect Transistor) and the ability of the FET (Field-Effect Transistor) to withstand it. A module lifetime level of fault events is established based upon the durability of the FET (Field-Effect Transistor). If the total tolerance level is determined to be 600 fault events, the 3 predefined levels would be 200, 400 and 600 fault events.

When each tolerance level is reached, the continuous DTC that was stored on the first failure cannot be cleared by a command to clear the continuous DTCs. The module does not allow this code to be cleared or the circuit restored to normal operation until a successful self-test proves that the fault has been repaired. After the self-test has successfully completed (no on-demand DTCs present), DTC U1000:00 and the associated continuous DTC (the DTC related to the shorted circuit) automatically clears and the circuit function returns.

When the first or second level is reached, the continuous DTC (associated with the short circuit) sets along with DTC U1000:00. These DTCs can be cleared using the module on-demand self-test, then the Clear DTC operation on the scan tool (if the on-demand test shows the fault corrected). The module never resets the fault event counter to zero and continues to advance the fault event counter as short circuit fault events occur.

If the number of short circuit fault events reach the third level, then DTC U3000:49 sets along with the associated continuous DTC. This DTC cannot be cleared and the module must be replaced.

The only RFA (Remote Function Actuator) module FET (Field-Effect Transistor) protected output circuits for PATS (Passive Anti-Theft System) are the backup transceiver circuits.
pro multis · About Operation CHARM