Replaced the ignition cylinder and now it will not start?

2011 GMC TERRAIN
124,000 MILES • 3.0L • V6 • 4WD • AUTOMATIC
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TONIMARIE8913
I lost my only key with key fob, so I swapped out cylinder with new one with keys already programmed to it but, it won't allow me to start the car. It came with the 10*10*10 instructions but no luck.
Oct 12, 2024 at 8:21 AM
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JACOBANDNICKOLAS
  • ✓ASE Certified Mechanic
  • 110,193 POSTS
  • ASE Certified Mechanic
Hi,

The key and lock cylinder you used may have worked on a different vehicle, but the ECU needs programmed to recognize the new part.

I attached the directions below. Note that you will need a scan tool that can communicate and initiate the relearn.

Let me know if this helps.

Take care,

Joe

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Oct 12, 2024 at 9:11 PM
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