Self-activated alarm in BMW – what is the reason?

BMW driver question

For the past few days, an alarm has been going off after closing my BMW. It happens a minute after closing, but only the hazard lights flash, no beep. I’ve tested this fault and if I don’t stop it, the phenomenon may continue continuously.

I’ve already checked under the hood, and I don’t have a left-side tailpiece. I even disconnected the fuse at the micro filter and also nothing. Do you guys know how to solve this bothersome fault? Thank you in advance for your reply.

The problem was on a 2000 BMW 3 E46, but it may happen on other models as well.

BM Cars service response

Without having the VIN number of the vehicle, we do not know if it was factory equipped with an alarm or if there was a retrofit. An alarm without a siren can only activate if it is intentionally activated or damaged. If the alarm is triggered every time, it is necessary to diagnose which limit switch or signal from the locks, in the case of the doors, gives the trigger signal to the alarm.

In the case of a BMW factory alarm, this is to be checked during vehicle diagnostics. In the case of add-on alarms, documentation is needed on the type and how the alarm was installed.

In each of the cases described, a visit to the service center is necessary to accurately diagnose the fault.

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