In view of the maintenance history and the reasons for the trigger of this inquiry, if the USIS does not receive the door is illegally opened signal is not alarm, the problem should also appear in the upstream signal generation part.
To buy Yanhua BMW FEM Key Programmer
Re-check the door lock block, FEM and the line between the two, are normal, but check the line found that the user unauthorized connection in the line an inverter power supply, it seems that the cause of this failure should also be interference. When Yanhua key programmer into the work, the interference signal through the lock block to reach the FEM wire, so FEM mistaken for the door was illegally opened, so it triggered the alarm.
Troubleshooting: communicate with the user, the temporary removal of inverter power, after a period of time after the user's use, the return visit to determine the failure no longer occurs.
Summary: BMW FEM Key Programmer can be seen from the failure, in the actual maintenance, electromagnetic interference caused by the failure cannot be ignored, especially in the electronic control unit of many vehicles, this fault is more common.
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