C Klasse Alarm System Problem

I had something similar happen with my C Klasse, though I can't say for sure if it's the exact same issue. Was there recently any power failure, or maybe a battery issue? Have you checked the alarm sensor? Because in my case, the problem was related to the alarm control being coded to activate the optical locking (indicators). I am not sure if it is the same, but that is what happened to me.

Power failure... hmm, not that I'm aware of. Battery seems fine, but I'll double-check it. When you say 'coded to activate optical locking,' what exactly do you mean? Was it a setting that got changed somehow?

Well, what I mean is that the alarm system was trying to use the indicators in a way that caused the system to fail. I am not sure how that happened. I would be guessing it is similar, because you have the same symptoms and error stored. Honestly, I would take it to a workshop. It is probably a small fix.

Thanks for the insight! You were spot on. Turns out the alarm system was indeed coded for the optical locking. Cost me 45€ to get it sorted at the workshop. Appreciate the help!