Keyless Entry: Description and Operation

Keyless Entry System Description and Operation

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 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 (RCDLR). The RCDLR interprets the signal and activates the requested function via a serial data message. A low transmitter battery or radio frequency (RF) interference from aftermarket devices, such as 2-way radios, power inverters, computers, etc., may cause a system malfunction. High RF traffic areas, such as gas stations that use pay-at-the-pump RF transponders, may also cause interference that could lead to a malfunction. Keyless entry allows you to operate the following components:

* The door locks
* The illuminated entry lamps.
* The panic alarm.
* Remote vehicle start (RVS).

The keyless entry system has the following main components:

* The keyless entry transmitters
* The body control module (BCM)
* The remote control door lock receiver (RCDLR)-When you press a button on the transmitter, the transmitter sends a signal to the RCDLR. The RCDLR receives the signal and sends a X Link serial data message requesting the appropriate function from the BCM.

Unlock Driver Door Only

Momentarily press the UNLOCK button in order to perform the following functions:

* Unlock the driver door only.
* Illuminate the interior lamps for approximately 20 seconds or until the ignition is turned ON.
* Flash the park lamps if the ignition is turned OFF and the doors are closed.
* Identify the driver to the radio-The radio will then revert to the station presets, the last station, the last volume settings, and the last playback mode used by that driver.

Unlock All Doors - Second Operation

Momentarily press the UNLOCK button a second time, within 5 seconds of the first press, in order to perform the following functions:

* Unlock all of the doors.
* Illuminate the interior lamps for approximately 20 seconds or until the ignition is turned ON.

Lock All Doors

Press the LOCK button in order to perform the following functions:

* Lock all of the doors.
* Immediately turn OFF the interior lamps.
* Flash the park lamps if the ignition is OFF and the doors are closed, if turned ON via personalization.
* Chirp the horn if the ignition is OFF and the doors are closed, if turned ON via personalization.

Panic Alarm Function

A single press of the panic button performs the following functions:

* Illuminates the interior lamps.
* Chirp pulses the horn.
* Flashes the daytime running lamps for 30 seconds or until the following conditions occur:

- The panic button is pressed again.
- The ignition switch is turned to the RUN position with a valid key.

Remote Vehicle Start

The Remote Vehicle Start function allows the customer to start the vehicle while not in the car. The distance the customer can be away from the vehicle and operate this feature from a distance of up to 60 meters or 197 feet. The Remote Vehicle Start feature is started by pressing and releasing the lock button and then pressing and holding the remote vehicle start (RVS) buttons on the key fob. The turn signal lamps will flash if this feedback is enabled on to indicate the vehicle has received the Remote Start Request. Once the vehicle has been started, there is visible feedback. There are vehicle conditions which will prevent a remote start, for example if the hood is not closed or the key is in the ignition. The Remote Vehicle Start feature once activated is allowed to run for 10 minutes. At any time during this 10 minute time the 10 minute time-out can be reset once. This feature is called a Remote Vehicle Start Continue. This allows a maximum of 20 minutes of engine running via the Remote Vehicle Start feature without a reset. If the Remote Vehicle Start Continue is done at 7 minutes into the initial 10 minute time-out, a total of 17 minutes of engine running would occur. A remote vehicle start, once active, can be stopped by pressing a dedicated RVS button on the key fob or by pressing the Vehicle Hazard switch located inside the vehicle. The following will also abort a remote start, using an invalid passkey, force rotating the ignition, force shifting out of park. Remote start will also be stopped if any DTCs that turn ON the SES/MIL are stored in history or current status.

Customer Programming Method for Enabling/Disabling the RVS Feature

Using the driver information center (DIC), the RVS feature can be DISABLED and ENABLED just like other items programmable via the DIC.

Remote Vehicle Start Features That Allow A Remote Vehicle START/CONTINUE

* The remote vehicle start (RVS) feature must be enabled.
* A remote vehicle start request command is received by the body control module (BCM).
* The hood ajar switch status is closed.
* The number of remote start attempts is less than 3.
* The key is not in the ignition.
* The remote start voltages are within proper operating ranges 6-16 volts.
* There are no DTCs or serial data communication failures with RVS related systems.
* The transmission status is Park/Neutral and the vehicle speed is zero.

Conditions to Stop A Remote Vehicle Start

* Hood ajar switch status is - OPEN.
* Inserting the key in the ignition and turning the key to any non-off power modes, and returning the key to the OFF position
* The remote vehicle start (RVS) time has elapsed or timed out.
* The RVS master receives a run abort message from the engine control module (ECM).
* Hazard shutoff switch status is - ACTIVE.
* By content theft deterrent (CTD) system, if equipped, and alarm status becomes Violated
* RVS system voltage out of range, under 6 volts or over 16 volts
* DTCs set for any related systems, or serial data communication failure for any modules that support the RVS function

If the RVS master stops a remote vehicle start for any of these conditions, further remote vehicle starting is not allowed until a RVS RESET has occurred.

A RVS Reset occurs when, in an ignition switch vehicle, the key is inserted and rotated into the Run position, power mode of RUN is seen, and ECM Vehicle Theft Fuel Continue is received over serial data and passes VTD criteria.

This action results in resetting the RVS counters to MAX starts allowed and the RVS Attempts to 0.