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Home >> GMC >> 1999 >> Yukon Base, RWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 249 (Engine Controls - Self-Diagnostics - 4.3L) >> Programming >> Theft Deterrent Password Learn Procedure >> 30-Minute Learn Procedure
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30-Minute Learn Procedure

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2003 GMC Sonoma, 2003 GMC Safari, 2003 GMC Jimmy, 2003 Chevrolet S10 Pickup, and 2003 Chevrolet Blazer. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition on, with engine off.
  2. Attempt to start the engine, then release the key to ON (vehicle will not start).
  3. Observe the SECURITY telltale, after approximately 10 minutes the telltale will turn OFF.
  4. Turn ignition off, and wait 5 seconds.
  5. Repeat steps  1- 4 two more times for a total of 3 cycles/30 minutes (the vehicle is now ready to relearn the Passlock™ Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK).
    6. NOTE: The vehicle learns the Passlock™ Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. Turn ignition off before attempting to start the engine.
  6. Start engine (vehicle has now learned the Passlock™ Sensor Data Code and/or password).
  7. With scan tool, clear any DTCs if needed (history DTCs will self clear after 100 ignition cycles).
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