Keyless Entry: Description and Operation

The Keyless Entry System allows a driver to operate several vehicle features from outside the car using a hand-held radio transmitter. The transmitter operates in the UHF band; it sends coded signals to the Remote Function Actuator (RFA) MODULE. The RFA module detects and decodes the signals and issues signals to control the door locks, trunk release, theft deterrent (if equipped) and illuminated entry. These systems also can be operated in the usual manner; for example, the door locks still respond to the power door lock switches.

To perform any operation. the RFA module must receive a Valid Vehicle Access Code (VAC)from the transmitter.

When the RFA module receives a command to lock or unlock the doors. it provides a signal to the Body Control Module (MALL,) to perform the lock or unlock function. The RFA module controls the LH Door Lock Isolation Relay to provide for two door lock modes drivers door unlock or all door unlock When the RFA module receives a command to open the trunk lid sound the horn, or flash the perimeter lights, it sends a signal to the corresponding relay to perform the appropriate function The RFA controlled circuits are covered as follows:
^ Refer to Power Door Locks for a detailed circuit description of door lock circuits. Power Locks
^ Refer to Release System for a detailed description of the trunk lid release circuits. Trunk / Liftgate
^ Refer to Horn for a detailed description of the horn circuits. Horn
^ Refer to Headlamp for a detailed description of the Headlamp circuits. Headlamp
^ Refer to Interior Lamps for a detailed description of interior lighting circuits. Lighting and Horns
^ Refer to Theft Deterrent System for a detailed description of the Universal Theft Deterrent System circuits. Antitheft and Alarm Systems
^ Refer to Retained Accessory Power for a detailed description of the Retained Accessory Power (RAP) circuits.