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Ask Dave Nova Your Own Question
Dave Nova
Dave Nova, GMC Technician
Category: GMC
Satisfied Customers: 19452
Experience:  ASE Master Certification. GM World Class Certification
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1999 gmc yukon how to reset anti theft

Customer Question

1999 gmc yukon how to reset anti theft
Submitted: 5 years ago.
Category: GMC
Expert:  Dave Nova replied 5 years ago.
Hello and thank you for using Justanswer. My name is David and I will do my best to help you with your GMC problem.

Does engine start and then stall? Is security light staying on or flashing when attempting to start?
Customer: replied 5 years ago.
yes starts an stalls.the light is staying on .just replaced the heads had battery unhooked.
Expert:  Dave Nova replied 5 years ago.
Try the reset procedure again. I have it listed below for you. Let me know what happens.

30 Minute Learn Procedure
1. Turn ON the ignition, with the 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 OFF the ignition, and wait 5 seconds.
5. Repeat steps 1 through 4 two more times for a total of 3 cycles/30 minutes, the vehicle is now ready to relearn the PASSLOCK(TM) Sensor Data Code and/or passwords on the next ignition switch transition from OFF to CRANK.

IMPORTANT: The vehicle learns the PASSLOCK(TM) Sensor Data Code and/or password on the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.

6. Start the engine. The vehicle has now learned the PASSLOCK(TM) Sensor Data Code and/or password.
Customer: replied 5 years ago.
did not work
Expert:  Dave Nova replied 5 years ago.
Since the relearn did not work, the problem is likely going to be a bad passlock sensor. This sensor is located in the upper steering column where the ignition lock cylinder inserts. Replacement of the sensor will likely be required to fix the problem.
Customer: replied 5 years ago.
Nope. I just fixed. turned the key to the on position, turned the turn signal left and right, the light went off, cranked the truck and it started. Thanks for the effort though.
Expert:  Dave Nova replied 5 years ago.
Glad it started working for you. May be a loose connection in the column, something to look out for if it happens again.