Keyless Entry System Description and Operation (With ATS)
Keyless Entry System Description and Operation (With ATS)
Keyless Entry System Description and Operation - Active
The keyless entry system is a vehicle entry device. The keyless entry system is used in conjunction with the door locks to unlock the vehicle. Keyless entry will lock/unlock a door or open the rear compartment lid when a corresponding button on the keyless entry transmitter is pressed. This is accomplished by the transmitter sending a radio frequency to the remote control door lock receiver antenna that has a direct link to the body control module (BCM). The BCM interprets the signal and activates the requested function or request the appropriate ECU to activate the function via a serial data message. A low transmitter battery or radio frequency interference from aftermarket devices, such as 2-way radios, power inverters, computers, etc., may cause a system malfunction. High radio frequency traffic areas, such as gas stations that use pay-at-the-pump radio frequency transponders, may also cause interference that could lead to a malfunction. Keyless entry allows you to operate the following features:
* Door lock/unlock
* Rear compartment lid release
* Illuminated entry lamps
* Panic alarm/Vehicle locator
* Remote vehicle start
* Automatic window express down, if equipped. Automatic window express up, if equipped
Keyless Entry System Description and Operation - Passive
Passive keyless entry allows entry to a locked vehicle without pressing any buttons on the keyless entry transmitter. You must only have the transmitter with you. The passive entry system use low frequency antennas in several different areas on the vehicle to determine the location of the transmitter. When passively opening a locked door or the rear compartment, you must have a programmed transmitter with you in your pocket, purse, or briefcase.
When a door handle is pulled or the rear compartment touch pad is pressed, the low frequency antenna sends out a challenge to the keyless entry transmitter. Because of the low frequency, communication range is limited. The antenna will emit the challenged in a one meter range. The transmitter must be within this range to receive the challenge. The transmitter receives this challenge and emits it's response as an RF message, which is received by the remote control door lock receiver. If the response is correct, the door or rear compartment will unlock and open.
As a customer convenience feature, the keyless entry system will notify the driver if the transmitter has been left in the vehicle after exiting by chirping the vehicle horn three times. This may be turned off using vehicle personalization. Also, if the transmitter is left in the vehicle after the central door lock switch has been used to lock the vehicle, the driver door will remain unlock after exiting the vehicle. This is intended to prevent locking the transmitter in the vehicle and being unable to access it.
Keyless Entry System Description and Operation - Keyless Start
The keyless start portion of the keyless entry system allows vehicle starting, having only the transmitter as your key. The keyless start system use low frequency antennas in three different locations on the vehicle to determine the location of the transmitter. Multiple antenna are used to ensure complete coverage of the vehicle interior and rear compartment. When using the keyless start system, a programmed transmitter must be in the vehicle's interior, in the driver's pocket, purse, or briefcase.
When the ignition mode switch is pressed, the low frequency antennas emit a challenge to the keyless entry transmitter. The transmitter receives this challenge and emits it's response as an RF message, which is received by the remote control door lock receiver. If the response is correct, vehicle starting will be allowed. If RF communication is interrupted, a "No Remote Detected" message will be displayed on the DIC. In these cases, the transmitter can be placed in the transmitter pocket located in the center console, under the cupholder. The immobilizer antenna coil is located directly beneath the transmitter pocket. Placing the transmitter in the pocket will create a low powered coupling between the transmitter and immobilizer antenna, allowing communications to occur and enabling vehicle starting.
The keyless entry system has the following components:
* Keyless entry integrated key/transmitter
* Driver and front Passenger door antennas (part of the door handle assembly)
* Driver and front Passenger door lock sensors (part of the door handle assembly)
* Rear fascia antenna
* Front console antenna
* Rear console antenna
* Trunk antenna (rear compartment)
* Body control module (BCM)
* Keyless entry control module
* Immobilizer antenna coil assembly
* Remote control door lock receiver
Keyless Entry Transmitters
By operating any of the exterior door handles, a nearby transmitter is challenged by a keyless entry antenna. The transmitter will send an RF response to the remote control door lock receive, which communicates with the BCM. The BCM will interpret this communication and either allow entry into the vehicle or deny it.
Door Antennas
The keyless entry door antennas are used to transmit low frequency communications to the keyless entry transmitters.
The keyless entry door antennas are located in the left front and right front exterior door handle bracket. The antennas are serviced as part of the door handle assembly. The antennas are controlled by the keyless entry control module. When the exterior door handle is operated, the respective antenna will send out a challenge to the keyless entry transmitter, which begins the passive entry communications.
Rear Fascia Antenna
The rear fascia antenna is used to transmit low frequency communication to the keyless entry transmitters for entry to rear compartment.
The rear fascia antenna is located behind the rear fascia. The antenna is controlled by the keyless entry control module. When the rear compartment touch pad is pressed, the antenna sends out a challenge to the keyless entry transmitter, which begins the passive entry communications.
Front Console Passive (Instrument Panel) Antenna
This antenna is located in the lower instrument panel near the front of the center console.
The front console antenna is used for vehicle starting functions. When the ignition mode switch is pressed, the antenna is energized or "pinged". This emits a low frequency challenge signal that is received by the keyless entry transmitter. The transmitter will then reply to this challenge with a response and, if correct, vehicle starting will occur.
Rear Console Antenna
This antenna is located in the rear of the center console.
The rear console antenna is used for vehicle starting functions. When the ignition mode switch is pressed, the antenna is energized or "pinged". This emits a low frequency challenge signal that is received by the keyless entry transmitter. The transmitter will then reply to this challenge with a response and, if correct, vehicle starting will occur.
Rear Compartment Antenna
This antenna is located in the center of the rear compartment metal floor pan, near the seatback.
The rear compartment antenna is used for vehicle starting functions. When the ignition mode switch is pressed, the antenna is energized or "pinged". This emits a low frequency challenge signal that is received by the keyless entry transmitter. The transmitter will then reply to this challenge with a response and, if correct, vehicle starting will occur.
Immobilizer Antenna Coil Assembly
The immobilizer coil assembly is located in the center console, directly beneath the transmitter pocket. If the transmitter battery is dead, weak, or the RF signal is being interrupted, the transmitter may be placed in the pocket to create a low powered coupling between the transmitter and immobilizer antenna, allowing communications to occur and enabling vehicle starting.
The immobilizer antenna coil is controlled by the BCM. The immobilizer control module is also active when learning vehicle keys.
Keyless Entry Control Module
The keyless entry control module is a multi-function module which performs the following keyless entry system functions:
* Activating vehicle antennas for passive keyless entry functions
* Activating vehicle antennas for keyless start functions
* Backup control for the ECM accessory wakeup and the run/crank relay
* If equipped, controls the electronic steering column lock
* Receiver of the door handle switch inputs and the lock sensor inputs and door open switch (not the door ajar switch)
* Control the door unlatch motors
* Ignition mode switch monitoring
Body Control Module (BCM)
The BCM is a multi-function module that performs the following functions:
* Receive and authenticate active transmitter and keyless start signals from the remote control door lock receiver
* Determines the functionality requested by the transmitter signal
* Performs the function requested by the transmitter signal
Unlock Driver Door Only - Active
Momentarily press the transmitter UNLOCK button in order to perform the following functions:
* Unlock only the driver door
* Illuminate the interior lamps for a determined length of time, or until the ignition is turned ON
* Flash the exterior lights, if enable through personalization
* Disarm the Content Theft Deterrent (CTD) system
* Deactivate the CTD system when in the alarm mode
Unlock All Doors - Second Operation - Active
Momentarily press the transmitter UNLOCK button a second time, within 5 seconds of the first press, to perform the following function:
Unlock the remaining doors
Unlock Driver Door Only - Passive
If enabled through personalization, approach the driver door with a valid keyless entry transmitter and pull the door handle to perform the following functions:
* Unlock and open only the driver door when door handle is operated
* Disarm the CTD system, if equipped
* Deactivate the CTD system when in the alarm mode
Unlock All Doors - Passive
Approach any non driver door (front or rear) or if enabled through personalization, driver door with a valid keyless entry transmitter to perform the following functions:
* Unlock all vehicle doors when the approached door handle is operated
* Only opens door whose door handle is pulled
* Disarm the CTD system, if equipped
* Deactivate the CTD system when in the alarm mode
Lock All Doors - Active
Press the transmitter LOCK button to perform the following functions:
* Lock all vehicle doors
* Immediately turn off the interior lamps
* Flash the exterior lights, if enabled through personalization
* Chirp the horn, if enabled through personalization
* Arm the CTD system
Lock All Doors - Passive
Exit the vehicle (with ignition off) with the keyless entry transmitter to automatically perform the following functions, if equipped.
* Lock all vehicle doors after a delay
* Flash the exterior lights, if enabled through personalization
* Chirp horn, if enabled through personalization
* Arm the CTD system
When all doors are closed, they can also be locked from the exterior by touching the lock sensor on the outside of a front door handle while having a valid transmitter in range. This function is only active for several minutes after all doors are closed to save battery life.
If more than one keyless entry transmitter is within a vehicle and the Keyless Entry System detects that one or more transmitters have been left in the vehicle after vehicle is locked, any transmitter left within the vehicle will be temporarily deactivated until:
* A button on the deactivated key fob is pressed (will only activate the fob whose button is pressed)
* A passive unlock of vehicle occurs
* Change in power mode occurs
Rear Compartment Lid Release - Active
If the vehicle transaxle is in PARK or NEUTRAL and the ignition is in the OFF position, a single press of the transmitter rear compartment release button will open the rear compartment lid.
Rear Compartment Lid Release - Passive
Approach the rear of the vehicle with a valid keyless entry transmitter. Press the rear compartment lid release touch pad. The rear compartment lid will open.
If vehicle is not equipped with trunk antenna, a keyless entry transmitter left inside the truck will allow the trunk to be reopened at any time. This feature will not allow a customer to lock the transmitter in the trunk.
If vehicle has a trunk antenna and one or more transmitters are left in the trunk or interior of the vehicle, those transmitter(s) will be deactivated when the vehicle becomes locked.
Vehicle Locator/Panic Alarm/Active
A single press of the panic button performs the following functions. Some functions may be dependent on personalization settings:
* Pulses the horn three times
* Flashes the exterior lamps three times
A press and hold of the panic button performs the following functions:
* A press and hold of the panic button performs the following functions:
* Pulses the horn and flashes the parking lamps for 30 second or until the following conditions occur:
- The panic button is pressed
- The ignition switch is turned to the RUN position with a valid key