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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 >> 10-Minute Learn Procedure
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10-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.
NOTE: This procedure requires a Tech 2 scan tool and a Techline terminal with current SPS (Service Programming System) software.
  1. Connect the Tech 2 to the vehicle.
  2. Select "Request Information" under "Service Programming".
  3. Disconnect the Tech 2 from the vehicle and connect it to a Techline™ terminal.
  4. On the Techline™ terminal, select "Theft Module Re-Learn" under "Service Programming".
  5. Disconnect the Tech 2 from the Techline™ terminal and connect it to the vehicle.
  6. Turn ignition on, with engine off.
  7. Select "VTD Re-Learn" under "Service Programming".
  8. Attempt to start engine, then release the key to ON (vehicle will not start).
  9. Observe the SECURITY telltale, after approximately 10 minutes the telltale will turn OFF (the vehicle is now ready to relearn the Passlock™ Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK).
  10. Turn ignition off, and wait 5 seconds.
  11. Start engine (the vehicle has now learned the password).
  12. With the Tech 2 (scan tool), clear any DTCs.
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