Handles, Locks, Latches and Entry Systems - With Intelligent Access (IA)

Handles, Locks, Latches and Entry Systems - With Intelligent Access (IA)

Principles of Operation

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

The Remote Function Actuator (RFA) module receives inputs and delivers outputs to many of the electronically controlled features of the vehicle. The RFA (Remote Function Actuator) module constantly monitors the system under its control and reports an issue in the form of a DTC.

Power Door Locks

Regardless of the key position, the RFA (Remote Function Actuator) module and the Driver Door Module (DDM) are supplied voltage at all times. When the RFA (Remote Function Actuator) module receives a signal from the Intelligent Access (IA) key through the Remote Functions Receiver (RFR) module, the keyless entry keypad, or the RH door lock control switch, it sends a ground signal to the lock and unlock relays. When the LH door lock control switch is pressed, the DDM (Driver Door Module) receives the lock or unlock signal. The DDM (Driver Door Module) sends a request through the Medium Speed Controller Area Network (MS-CAN) to the RFA (Remote Function Actuator) module to lock or unlock the doors.

Luggage Compartment Lid Release

NOTE: When using the IA (Intelligent Access) key, 2 presses of the IA (Intelligent Access) key luggage compartment lid release button (within 3 seconds) are required to release the luggage compartment lid.

The luggage compartment lid release system is disabled when the vehicle speed exceeds 8 km/h (5 mph). The luggage compartment lid latch releases the luggage compartment lid when the customer requests it be opened using either the IA (Intelligent Access) key, the keyless entry keypad, or the interior luggage compartment lid release switch. When the RFA (Remote Function Actuator) module receives a signal to release the luggage compartment lid, the RFA (Remote Function Actuator) module supplies voltage to the luggage compartment lid latch. The luggage compartment lid latch then actuates to release the luggage compartment lid.

Driver Door Intelligent Access (IA) Feature

The driver door IA (Intelligent Access) feature allows the driver door to be unlocked without having to use the door lock cylinder or the RKE (Remote Keyless Entry) transmitter. With a programmed IA (Intelligent Access) key within 1 m (3 ft) of the driver door handle outside of the driver door, touch any button on the keyless entry keypad, and the driver door unlocks (with stepped unlock enabled), or unlocks all doors (if stepped unlock is disabled). When the RFA (Remote Function Actuator) module detects keyless entry keypad activity, it activates the low frequency antenna in the driver door handle. The low frequency antenna sends out a signal to the IA (Intelligent Access) key. The low frequency signal activates the IA (Intelligent Access) key and the IA (Intelligent Access) key then sends a high frequency signal back to the RFR (Remote Functions Receiver) module. The RFR (Remote Functions Receiver) module interprets the high frequency signal from the IA (Intelligent Access) key and sends the information to the RFA (Remote Function Actuator) module. If the RFA (Remote Function Actuator) module determines that it is a programmed key, it will unlock the driver door or all doors.

Luggage Compartment Intelligent Access (IA) Feature

The luggage compartment IA (Intelligent Access) feature allows the luggage compartment lid to be released without having to use the interior luggage compartment lid release switch or the keyless entry keypad. With a programmed IA (Intelligent Access) key within 1 m (3 ft) outside of the luggage compartment lid, press the exterior luggage compartment lid release button on the luggage compartment lid, and the luggage compartment lid latch releases. When the RFA (Remote Function Actuator) module detects a signal from the exterior luggage compartment lid release switch, it activates the low frequency antenna in the rear bumper cover. The low frequency antenna sends out a signal to the IA (Intelligent Access) key. The low frequency signal activates the IA (Intelligent Access) key and the IA (Intelligent Access) key then sends a high frequency signal back to the Remote Functions Receiver (RFR) module. The RFR (Remote Functions Receiver) module interprets the high frequency signal from the IA (Intelligent Access) key and sends the information to the RFA (Remote Function Actuator) module. If the RFA (Remote Function Actuator) module determines that it is a programmed key, it will release the luggage compartment lid.

Remote Keyless Entry (RKE)

The RFR (Remote Functions Receiver) module receives and interprets radio frequency signals from the IA (Intelligent Access) keys. The RFR (Remote Functions Receiver) module processes the signals and then communicates the command to the RFA (Remote Function Actuator) module. The RFA (Remote Function Actuator) module sends a request to the SJB (Smart Junction Box) over the MS-CAN (Medium Speed Controller Area Network) for the illuminated entry feature to turn the interior lamps on when an unlock command is received. If a lock command is received, the illuminated entry feature turns off.

The IA (Intelligent Access) key supplies a signal to the RFA (Remote Function Actuator) module when any button is touched. The RFA (Remote Function Actuator) module then supplies voltage to the appropriate door lock actuator(s) to lock or unlock the doors. The IA (Intelligent Access) key can also be used to release the luggage compartment lid or activate the panic alarm. The IA (Intelligent Access) key also causes the RFA (Remote Function Actuator) module to send an MS-CAN (Medium Speed Controller Area Network) message to the Driver Seat Module (DSM) to activate all memory features to the positions associated with the IA (Intelligent Access) key being used.

Keyless Entry Keypad

The keyless entry keypad is hardwired to the RFA (Remote Function Actuator) module. The RFA (Remote Function Actuator) module interprets the inputs from the keyless entry keypad and then controls the associated operation. The keyless entry keypad is illuminated for 5 seconds when any button is touched and also anytime that the courtesy lighting is on. The RFA (Remote Function Actuator) module requests the illuminated entry feature to turn the interior lamps on when a valid entry code is received. If a lock all doors code is entered, the illuminated entry feature turns off.

NOTE: The keyless entry keypad does not lock the doors if the driver door is ajar.

NOTE: The keyless entry keypad does not lock the doors and the driver door IA (Intelligent Access) does not function if the driver door is ajar.

The keyless entry keypad supplies a signal to the RFA (Remote Function Actuator) module when the buttons are pressed. The RFA (Remote Function Actuator) module then supplies voltage to the appropriate door lock actuator(s) to lock or unlock the doors. The keyless entry keypad can also be used to release the luggage compartment lid. The keyless entry keypad also causes the RFA (Remote Function Actuator) module to send an MS-CAN (Medium Speed Controller Area Network) message to the Driver Seat Module (DSM) to activate all memory features to the positions associated with the personal entry code entered on the keypad.

Field-Effect Transistor (FET) Protection

Field-Effect Transistor (FET) is a type of transistor that when used with module software can be used to monitor and control current flow on module outputs. The FET (Field-Effect Transistor) protection strategy is used to prevent module damage in the event of excessive current flow.

The RFA (Remote Function Actuator) module utilizes an 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 circuit for the handles, locks, latches and entry systems is the keypad illumination circuit CPK28 (WH/GN).