Aygo Alarm System Error

Could be a few things. Have you checked the battery voltage? A weak battery can cause electrical gremlins, especially with the alarm system. It might be throwing errors because it's not getting enough power. Is the error code specific? Knowing it could narrow down the cause. Any other electrical issues, like dimming lights or slow starting?

I tested the battery and it seems fine. The error code requires specialized equipment to retrieve. Could a faulty sensor, perhaps related to the door locking mechanism, trigger a fault within the alarm system? Or could a ground issue be a factor?

A faulty door sensor is possible, but less likely to cause a complete alarm system failure. A ground issue could definitely be a factor, but those are usually harder to diagnose without proper tools. I still suspect a coding or module issue. I'd recommend visiting a workshop that specializes in Toyota vehicles to have them properly diagnose the problem. They should be able to read the error code and pinpoint the exact cause.

I visited a local workshop. The alarm system was erroneously coded to activate the optical locking upon triggering the alarm. Recoding the system resolved the malfunction. The total cost was 45€.