This TSB applies to all BMW vehicles equipped with DWA Alarm (Option 302). When troubleshooting a customer complaint that the DWA (anti-theft alarm system) triggers unexpectedly, stored fault codes may be misleading and result in incorrect repair.

The first check must be to check the alarm counter, which shows the component responsible for the false alarms and the alarm frequency.

The alarm counter is checked using the BMW diagnosis equipment as follows:

• Most bus vehicles: “Function selection/Complete vehicle/Body/Locking and security functions/Burglar alarm system/DWA activations.”
• I-bus vehicles: The input responsible for alarm triggering is stored in the alarm memory in the ZKE (General Module). The alarm memory can be read out with the “short test” or with “read fault memory” in the diagnosis program.

Continue troubleshooting based on the results from the alarm counter check.