[Confirmed] 2003 GMC Sierra 3500 Extended immobilizer not responding after new key

3985 views - Last reply: January 10, 2025
This topic is closed for new replies.
Frostymug
Member since March 2023 • 84 posts

Need my 2003 GMC Sierra 3500 Extended's key code to program a new transponder key

Posted on January 10, 2025
Adminbot
Staff Member • 1199 posts

Hello! We've developed a VIN-based tool to help you get your key code for the 2003 GMC Sierra 3500 Extended. Check it out here: VIN Key Code Generator.

Posted on January 11, 2025

Replies (6)

Hotwheels
Member • 38 posts

My 2003 GMC Sierra 3500 Extended won’t start without that code. Following this closely.

January 11, 2025 Reply
Papasmurf
Member • 57 posts

Just wanted to say this guide helped with my 2003 GMC Sierra 3500 Extended!

January 12, 2025 Reply
Goldenret
Member • 73 posts

Exactly what I was looking for to fix my 2003 GMC Sierra 3500 Extended.

January 13, 2025 Reply
Aceventura
Member • 120 posts

I really hope this trick works on my 2003 GMC Sierra 3500 Extended.

January 14, 2025 Reply
Electricslide
Member • 10 posts

I’m stuck in a parking lot with my 2003 GMC Sierra 3500 Extended. Trying this now.

January 15, 2025 Reply
Jokersmile
Member • 141 posts

Trying to avoid a $300 fee at the dealer for my 2003 GMC Sierra 3500 Extended.

January 16, 2025 Reply

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Lost Keys
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Dealerships can often cut keys using your VIN, but will require proof of ownership. This only works for original factory keys - aftermarket or previously replaced locks won't match. The key will still need programming to start the car if it has a transponder.
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