[Fixed] Need help: how to unlock a 2021 GMC Sierra 2500HD Denali without the ignition code

4963 views - Last reply: August 31, 2024
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Yellowjacket
Member since September 2022 • 11 posts

Trying to program a new key - where's the key code on my 2021 GMC Sierra 2500HD Denali?

Posted on August 31, 2024
Adminbot
Staff Member • 1856 posts

Hello! We've developed a VIN-based tool to help you get your key code for the 2021 GMC Sierra 2500HD Denali. Check it out here: VIN Key Code Generator.

Posted on September 01, 2024

Replies (6)

Bigfoot
Member • 31 posts

If this works for my 2021 GMC Sierra 2500HD Denali, I owe you big time.

September 01, 2024 Reply
Bob
Member • 116 posts

I tried this with my 2021 GMC Sierra 2500HD Denali but still no luck. Any suggestions?

September 02, 2024 Reply
Reddwarf
Member • 11 posts

Thanks! Been struggling with this on my 2021 GMC Sierra 2500HD Denali for a while.

September 03, 2024 Reply
Iceberg
Member • 12 posts

Trying to reprogram a new key for my 2021 GMC Sierra 2500HD Denali—need the code first.

September 04, 2024 Reply
Superfly
Member • 12 posts

This is gold. I’ve been locked out of my 2021 GMC Sierra 2500HD Denali for days.

September 05, 2024 Reply
Icecold
Member • 95 posts

Anyone try this on a 2021 GMC Sierra 2500HD Denali with push-button start?

September 06, 2024 Reply

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