Keyless Entry System Description and Operation: Notes

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Notes
WARNING: This page is about a different car, the 2003 Pontiac Grand Prix. However, it is still accessible from the selected car via links, so may be relevant.

The keyless entry system is a supplementary vehicle entry device. Use the keyless entry system in conjunction with a door lock key. Radio frequencies or discharged batteries may disable the system. Therefore, always carry a door lock key.

Keyless entry allows you to operate the following components:

  • The door locks
  • The rear compartment lid release
  • The illuminated entry lamps
  • The panic alarm (instant alarm)

The keyless entry system has the following main components:

  • The transmitters
  • The remote control door lock receiver (RCDLR)
  • The body control module (BCM)

The RCDLR communicates with the BCM through the keyless entry serial data circuit. When you press a button on a transmitter, the transmitter sends a signal to the RCDLR. The RCDLR sends a lock, unlock, or panic alarm request to the BCM depending on which button is pressed on the transmitter. The BCM receives the message from the RCDLR and performs the appropriate function.

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