Replaced the ignition cylinder and now it will not start?

2011 GMC TERRAIN

124,000 MILES • 3.0L • V6 • 4WD • AUTOMATIC

TONIMARIE8913

MEMBER
1 POST
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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

AUTOMOTIVE REPAIR CONTRIBUTOR
110,190 POSTS

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

See pics below.

Images (Click to enlarge)

Oct 12, 2024 at 9:11 PM