Principles of Operation
PRINCIPLES OF OPERATIONPower Locks
The power lock/unlock feature commands all of the vehicle doors, including the liftgate, to lock or unlock upon a command from the door lock control switch or remote keyless entry (RKE) transmitter or the RKE keypad. Power locking and unlocking of the doors functions independently of the key position, vehicle speed, or transmission position. The smart junction box (SJB) activates the power door lock relays to supply the correct power and grounds for the door lock actuators.
Autolock
The autolock feature locks all the doors when all the doors, including the liftgate, are closed, the brake pedal is pressed with the key in the ON position, and the vehicle speed exceeds 5 kph (3 mph). This feature relocks the doors (if any doors were open) after the brake pedal is pressed, once all the doors are read as closed and the vehicle speed exceeds 5 kph (3 mph). The door ajar switches are wired directly to the SJB. The autolock feature can be enabled/disabled through module configuration and the ignition cylinder methods.
Smart Unlock
The smart unlock feature prevents the driver door from locking with the key in the ignition lock cylinder. When the SJB receives a LOCK command from a door lock control switch, and the key is in the ignition lock cylinder with the driver door open, the SJB commands the driver door to unlock.
Remote Keyless Entry (RKE) Transmitter
Remote Keyless Entry (RKE) Transmitter:
The RKE transmitter can be programmed using the ignition lock cylinder method.
The RKE transmitter initiates the following electronic system functions:
- unlocks the driver door
- unlocks all doors
- locks all doors
- activates/deactivates the panic alarm
- commands the interior lamps on (when unlocking) and off (when locking)
- sounds the horn once when LOCK is pressed twice within 3 seconds and the doors are closed
The RKE transmitter has a minimum effective operating range of 10 m (33 ft).
Remote Keyless Entry (RKE) Transmitter Lock/Unlock Control - Unlock
This RKE transmitter feature provides lock/unlock functions independently of key position, vehicle speed, or transmission position. This RKE transmitter feature provides a 2-step process for unlocking the doors. Upon receipt of the first request for unlocking the doors, the SJB unlocks the driver door only. If another unlock command is received within 3 seconds of the first, the SJB unlocks all the doors.
Remote Keyless Entry (RKE) Transmitter Lock/Unlock Control - Lock
This RKE transmitter feature requests that all the doors be locked when the LOCK button on the RKE transmitter is pressed. On any press of the LOCK button with all the doors closed, this RKE transmitter feature commands 1 flash of the parking lamps. If any door is ajar, no flash occurs, indicating that all the doors were locked, but one or more doors are ajar. As soon as the last door is closed, the parking lamps flash once. If 2 presses of the LOCK button are received within 3 seconds, the horn chirps once and the parking lamps flash to indicate that all the doors are closed and locked. If any door is ajar and the second lock command is received within 3 seconds of the first, the RKE transmitter feature commands the horn to chirp twice without flashing the parking lamps to indicate that all the doors are locked, but 1 or more doors are ajar. When the key is in the ON or START position, no parking lamp flashes or horn chirp confirmations occur.
Panic Alarm
The panic alarm feature provides audible and visual alarms that are evident from the exterior of the vehicle. The panic alarm feature commands the parking lamps to flash and the horn to sound until deactivation. These outputs occur simultaneously. Activation of the panic alarm is accomplished by pressing the PANIC button on the RKE transmitter whenever the key is in the OFF or ACC position. At all other times this feature is disabled. Deactivation of an active panic alarm is accomplished by: 1) a second press of the remote transmitter PANIC button, 2) switching the key out of the OFF or ACC position or, 3) a period of 2 minutes and 45 seconds has elapsed since the initial activation.
Remote Keyless Entry (RKE) Keypad
The RKE keypad, located on the exterior of the driver door, provides a method for the customer to access their vehicle without a key or RKE transmitter. The RKE keypad feature:
- locks all doors and inhibits the door lock control switch unlock capability after 20 seconds (if the inhibit feature is enabled).
- unlocks only the driver door.
- unlocks all doors.
- programs/erases the customer key code.
The RKE keypad feature operates independently of the key position status, vehicle speed, or transmission position. When a keypad button is pressed, the RKE keypad buttons illuminate to provide better visibility. If LOCK ALL DOORS is entered or 5 seconds have elapsed since the last button press, the illumination is turned off.
Each vehicle equipped with an RKE keypad is programmed with a 5-digit entry code. This code is provided to the customer through a wallet card in the owner literature package. In addition, this code is available through a diagnostic tool. When entering codes each digit must be entered within 5 seconds of the previous button press.
Anti-Scan Feature
To provide added security, the RKE keypad is disabled for 1 minute after 35 button presses without a valid entry code being entered. The RKE keypad flashes during this 1-minute mode with all functionality disabled except for 7/8 and 9/0 still being allowed to lock the vehicle.
Anti-Scan is turned off after 1 minute of keypad inactivity.
Unlocking the Doors and Liftgate with the Remote Keyless Entry (RKE) Keypad System
To unlock the driver door, enter either the factory set code or the personal code (each digit must be pressed within 5 seconds of the prior digit). The interior lamps then illuminate.
To unlock all doors, enter either the factory set code or the personal code (driver door unlocks) and press the 3/4 control within 5 seconds.
Locking the Doors with the Remote Keyless Entry (RKE) Keypad System
It is not necessary to enter the factory set or personal code prior to locking all doors. To lock all doors, press the 7/8 and 9/0 controls at the same time.
SJB Protective Circuit Strategy
The SJB utilizes a protective circuit strategy for many outputs (for example, the headlamp output circuit). Output loads (current levels) are monitored for excessive current (typically short circuits) and are shutdown (turns off the voltage or ground provided by the module) when a fault is detected. A continuous DTC is stored at that time for the fault. The circuit will then reset after an ignition cycle or customer demand of the function (switching on the component). When an excessive circuit load recurs several times, the module shuts down the output until the fault condition has been repaired and a successful on-demand self-test has been carried out. At the same time, the continuous DTC that was stored on the first failure does not clear by a command to clear continuous DTCs. The module only allows this code to be cleared or the circuit restored to normal when a successful on-demand self-test proves the fault has been repaired. After the on-demand self-test has successfully completed (no on-demand codes present), the continuous code will have been cleared and the circuit function returns.