Eseries key battery warning

I had something similar happen with my E-Series. Is it struggling to start the engine too, or is it just the remote functions that are failing?

No, the engine starts fine, thankfully! It's purely the keyless entry and the remote locking/unlocking that are playing up. Does this sound like your issue?

Yep, sounds exactly like what I experienced. It’s almost certainly the key fob battery. I'd recommend getting it checked at a workshop; they can replace it and clear the error code for you.

Thanks for the tip! I replaced the battery. Cost me about 37€, but everything's working perfectly again! The error code is gone too. You were spot on!