Method 1 - No Tools Required

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Method 1 - No Tools Required
WARNING: This page is about a different car, the 2002 Oldsmobile Bravada, 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
  1. Close all the vehicle doors.
  2. Insert the ignition key into the ignition lock cylinder.
  3. Press and hold the door unlock switch.
  4. While holding the door lock switch in the unlock position, cycle the ignition ON, OFF, ON, OFF.
  5. Release the door unlock switch. The doors will lock and unlock to confirm the program mode.
  6. Press and hold the LOCK button and the UNLOCK button simultaneously on one transmitter. After a delay of approximately 15 seconds, the doors will lock and unlock to confirm the programming of that transmitter.
  7. Repeat the previous step to program up to four transmitters.
  8. Turn the ignition switch to the RUN position in order to exit the keyless entry transmitter mode.
  9. Operate the transmitter functions in order to verify correct system operation.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.