AMG GT Key Fob Battery Issue

Sounds like what happened with my AMG GT. It's probably the fob battery. Keyless entry usually goes first, then the range gets terrible, and eventually, it won't work. Have you tried the spare key? Does that one do the same thing? Has the battery been replaced before?

Good idea about the spare key. I'll test it. I haven't replaced the battery in either key since buying the car. Where's the battery located, and what type does the key use?

Using the spare is a good way to rule out other problems. If the spare works, it's almost certainly the fob battery. There's a release catch on the key fob to access the battery. Use a small screwdriver to gently pry it open. The battery is a CR2032. You can get them easily. If the spare key also fails, take it to a workshop to check the system, as there could be other issues.

The spare key worked! I replaced the fob battery in the original key for 37€, and everything is normal. Thanks for the quick help!