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 the vehicle doors 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 requests the appropriate control module 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
• Liftgate lock/unlock
• Power liftgate, if equipped
• Illuminated entry lamps
• Panic alarm/vehicle locator
• Remote vehicle 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 antennas 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. 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 transmitter
• Front console antenna
• Rear console antenna
• Rear compartment antenna
• Body control module (BCM)
• Keyless entry control module
• Immobilizer antenna coil assembly
• Remote control door lock receiver

The keyless entry transmitters are used to perform various entry functions while away from the immediate area of the vehicle. Keyless entry functions may work at up to 20 m (65 ft) away from the vehicle. Ambient conditions may affect the performance of the keyless entry transmitter and reduce the range at which keyless entry functions operate. Up to eight transmitters may be programmed to a single vehicle.

When pressing the ignition mode switch to change power mode or start the vehicle, a nearby transmitter is challenged by a passive keyless entry antenna. The transmitter will send an RF response to the remote control door lock receiver, which communicates with the BCM. The BCM will interpret this communication and if the transmitter response is valid, allow the vehicle to change power mode or start the vehicle.

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.

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.

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.

The remote control door lock receiver is control by and directly communicates with the body control module (BCM). When the transmitter receives a low frequency challenge from an antenna, it responds with an RF message. This RF message is received by the remote control door lock receiver and communicated to the BCM. If the RF message is a valid response to the low frequency challenge, vehicle starting will be allowed.

The keyless entry 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 transmitters.

The keyless entry control module is a multi-function module which performs the following keyless entry system functions:

• Activating vehicle antennas for keyless start functions
• Backup control for the ECM accessory wakeup and the run/crank relay
• Redundant power moding, in addition to the BCM
• Ignition mode switch monitoring

A vehicle operator may have the ability to perform some of the keyless entry functions using applications on personal devices such as smart phones. Refer to OnStar Description and Operation.

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

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 enabled through personalization
• Disarm the content theft deterrent system
• Deactivate the content theft deterrent system when in the alarm mode

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 and liftgate

Press the transmitter LOCK button to perform the following functions:

• Lock all vehicle doors and the liftgate
• Immediately turn off the interior lamps
• Flash the exterior lights, if enabled through personalization
• Chirp the horn, if enabled through personalization
• Arm the content theft deterrent system

Press and hold the power liftgate button to perform the following functions:

• Open or close the liftgate using the power liftgate function
• Flash the tail lamps
• Sound the interior power liftgate chime

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 mode is turned to the RUN position with a valid keyless entry transmitter

The remote vehicle start function allows engine starting while not in the vehicle. It also allows the vehicle HVAC system and other vehicle systems to enable, providing a comfortable vehicle upon entry. The HVAC system will operate in the following possible ways:

• If the vehicle is equipped with a manual HVAC system it will be on and operating in the same way that the settings were adjusted when the vehicle was last used.
• If the vehicle is equipped with an automatic HVAC system it will operate as necessary to meet the temperature setting it was left at. If the conditions are such that the system needs AC, rear defrost, or defrost then those functions will operate. The indicator lights for these functions will not illuminate even if the features are on.
• If the vehicle is equipped with an automatic HVAC system but the system is in manual mode then it will operate the same as a manual system equipped vehicle with the HVAC operating however it was adjusted when the vehicle was last used.

The turn signal lamps will illuminate to indicate the vehicle has received the remote start request. Each time a remote vehicle start is performed, the vehicle doors are locked, however they may then be unlocked/locked with the transmitter at any time. Only the first and second vehicle transmitters are able to control the remote vehicle start function. Any additional remote transmitters programmed to the vehicle will perform all other remote functions. Once activated, the engine is allowed to run for 10 minutes. The remote vehicle start time may be extended by an additional 10 minutes by again pressing and releasing the lock button and then pressing and holding the remote vehicle start buttons on the transmitter. This feature is called a remote vehicle start continue and allows a maximum of 20 minutes of engine running. If the remote vehicle start continue is performed at 7 minutes into the initial 10 minute time-out, a total of 17 minutes of engine running would occur. The remote vehicle start event may be suspended at any time by pressing only the remote vehicle start button on the transmitter or by entering the vehicle and turning ON the hazard lamps.

In between ignition cycles, only two remote vehicle start events may occur or be attempted. Once two events or attempts have been made, future remote vehicle start events will be suspended until the vehicle is started using the ignition.

On some vehicles, remote vehicle start may be enabled or disabled as a part of vehicle personalization by using the driver information center controls. Refer to the vehicle owners manual for more information.

The hood switch provides status of the hood to the BCM for remote vehicle start purposes. The switch is integrated into the hood latch assembly. The hood ajar switch provides 2 separate inputs to the BCM. These separate inputs allow the BCM to actively monitor for a hood ajar switch fault.

The BCM receives a signal from the keyless entry transmitter indicating a remote vehicle start request. The BCM uses the following inputs to verify the system is ready for a remote vehicle start event:

• Vehicle is not in valet mode
• Low fuel level indicator is not requested on
• All vehicle doors are closed
• Rear compartment lid is not ajar
• The hood is closed
• The doors are locked
• The hazard switch is OFF
• Battery reconnect has not occurred
• Vehicle power mode is correct

When the BCM determines all conditions meet those required for a remote vehicle start event, a message is sent via serial data to the ECM. The ECM relies on the remote vehicle start message from the BCM to enable remote vehicle start when the crank request signal is received. If the ECM does not receive a valid remote vehicle start message, it will not ground the control circuit of the crank relay and start the engine. While the ECM is in remote vehicle start mode it will cut fuel to the engine if any of the following additional conditions occur:

• Vehicle speed is greater than 0
• Transmission is not in P
• Excessive engine coolant temperature
• Low oil pressure
• The malfunction indicator lamp (MIL) is commanded ON
• Engine crank time is greater than 30 seconds
• Excessive engine speed
• Accelerator pedal position too high
• Remote start timer equals 0
• Immobilizer system indicates a theft attempt

Vehicle lock/unlock functions and remote vehicle start settings may be personalized for the vehicle. For functional descriptions and programming instructions, refer to the vehicle owners manual.