[Free Fix] Locked out - need key code help for MercedesBenz CClass C 300 Sedan

779 views - Last reply: September 08, 2024
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Where's the key code stored in a MercedesBenz CClass C 300 Sedan for making new keys?

Hello! We've developed a VIN-based tool to help you get your key code for the MercedesBenz CClass C 300 Sedan. Check it out here: VIN Key Code Generator.

Replies (6)

This just might solve my MercedesBenz CClass C 300 Sedan's ignition issue.

This thread might save my MercedesBenz CClass C 300 Sedan. Thanks everyone!

Got a dead key fob for my MercedesBenz CClass C 300 Sedan. Need the code badly.

My MercedesBenz CClass C 300 Sedan won’t start without that code. Following this closely.

Anyone have luck with this on a 2015 MercedesBenz CClass C 300 Sedan?

Still looking for a reliable way to find the key code on my MercedesBenz CClass C 300 Sedan.

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Key Fob Issues
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Key Fob Issues
1) Find the seam and pry open the fob (some have tiny screws) 2) Note battery orientation 3) Remove old battery (CR2032 is most common) 4) Insert new battery 5) Reassemble. Test all buttons - if issues remain, the fob may need reprogramming.
Lost Keys
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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