LandCruiser siren communication fault

I had something similar happen with my LandCruiser. Check the alarm controller, often located behind the glove box or under the driver's seat. Specifically, inspect the wiring harness and connectors. Are you getting any other error codes or unusual electrical behavior?

Thank you for the advice. Beyond the siren communication fault, no other error codes are present, and electrical behavior seems normal. Could you elaborate on the specifics of the wiring harness inspection you performed?

For me, it turned out to be a corroded connector pin on the alarm controller itself. I didn't catch it at first glance. Given that you have no other codes, I suspect that the defective cable or plug connection you mentioned might be it. Honestly, unless you're very comfortable with automotive electrics, a workshop might be the best bet. I took mine in eventually.

Understood. I appreciate the confirmation and your recommendation. I will proceed with a professional diagnosis. Repair cost amounts to 95€.