Modus Anti Theft Alarm Issue

That sounds familiar. I have a Modus too, and had a similar issue. Was there any recent power failure?

Power failure? We had a brief outage last week. Could that mess with the alarm system? What happened with yours?

The power failure might be related. In my case, the alarm started acting up shortly after a blackout. I tried a few things myself, but ended up taking it to a workshop. They sorted it.

I had a workshop take a look, and you were spot on about the power failure! The alarm system was coded to activate optical locking (indicators), and that glitched. Cost me 45€ to fix. Thanks for the hint!