[Solved] Key cloning didn’t work - 2003 GMC Sierra 2500 HD still needs code

2452 views - Last reply: August 03, 2024
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Where's the key code hidden on a 2003 GMC Sierra 2500 HD for key programming?

Hello! We've developed a VIN-based tool to help you get your key code for the 2003 GMC Sierra 2500 HD. Check it out here: VIN Key Code Generator.

Replies (5)

My 2003 GMC Sierra 2500 HD won’t start without that code. Following this closely.

This is exactly what I need for my 2003 GMC Sierra 2500 HD, thanks for posting!

I think my 2003 GMC Sierra 2500 HD has the same issue. Good to know I'm not alone.

Hope I’m not too late to try this on my 2003 GMC Sierra 2500 HD.

I’ve been locked out of my 2003 GMC Sierra 2500 HD all week. Hope this helps.

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