For 1990-2009 cars

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 doors when a corresponding button on the keyless entry transmitter is pressed. This is accomplished by the transmitter sending a radio frequency to the body control module (BCM). The BCM interprets the signal and activates the requested function. A low transmitter or vehicle 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 may also cause interference that could lead to a malfunction. Keyless entry allows you to operate the following components:

• | Door locks

• | Vehicle locator/panic alarm

• | Illuminated entry lamps

The keyless entry system has the following components:

• | Keyless entry transmitters

• | BCM

### Keyless Entry Transmitters

The keyless entry transmitters are used to lock and unlock the vehicle door while away from the immediate are of the vehicle. Transmitters will operate at a distance of up to 20 m (65 feet), except Japanese and South Korean vehicles, which are limited to 4 m (13 feet). Up to 4 transmitters may be programmed to a single vehicle.

### Body Control Module (BCM)

The BCM is a multifunction module that operates both the keyless entry system. When an RF message is received from a keyless entry transmitter, the BCM interprets this signal performs the specific function, i.e. door lock, door unlock, or vehicle locate.

### Unlock Driver Door Only

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 (CTD) system, if equipped

• | Deactivate the CTD system when in the alarm mode

### Unlock All Doors - Second Operation

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.

### Lock All Doors

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 content theft deterrent (CTD) system, if equipped

### Vehicle Locator/Panic Alarm

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

• | Pulses the horn three times

• | Flashes the parking lamps three times

A press and hold of the panic button performs the following functions:

• | Illuminates the interior lamps

• | 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

### Rolling Code

The keyless entry system uses rolling code technology. Rolling code technology prevents anyone from recording the message sent from the transmitter and using the message in order to gain entry to the vehicle. The term "rolling code" refers to the way that the keyless entry system sends and receives the signals. The transmitter sends the signal in a different order each time. The transmitter and the remote control door lock receiver (RCDLR) are synchronized to the appropriate order. If a programmed transmitter sends a signal that is not in the order that the RCDLR expects, then the transmitter is out of synchronization. This occurs after 256 presses of any transmitter button when it is out of range of the vehicle.

### Automatic Synchronization

The keyless entry transmitters do not require a manual synchronization procedure. If needed, the transmitters automatically re-synchronize when any button on the transmitter is pressed within range of the vehicle. The transmitter will operate normally after the automatic synchronization.