Rifter siren communication fault

I have a Rifter too, and had something similar happen a while back. Check the cable and plug connections to the siren itself. It could be a simple wiring issue.

Thanks, that's helpful. When you say siren connections, is that easy to get to, or am I going to be dismantling half the car? I'm not exactly a mechanic!

Sadly, on mine the access wasn't great. The issue sounds awfully similar to mine and in my case the defective plug connection was the reason why the error happened. I would strongly advise going to a workshop. After the repair which costed 95€ everything worked fine again.

Thanks so much for your help. I took it to a mechanic, and you were spot on! It was indeed a faulty connection to the siren. The final bill was 95€, just like you predicted. At least now my Rifter's alarm is working again. I really appreciate you sharing your experience!