For the investigation the device was analysed and the pcb mobi 3 was determined to be the cause of the reported problem.Its investigation in the laboratory revealed a faulty microprocessor, which is responsible for communication between the components of the device.The exact failure mechanism could not be determined because the logbook cannot be downloaded in the present failure case.In the event of a device failure, automatic ventilation, fresh gas dosing and monitoring functions are no longer available.Manual ventilation is still available.The printed circuit board was replaced and the unit was checked according to manufacturer's specification.No further deviations were found.The number of similar cases due to the same cause is within the expected range of the respective risk assessment and is therefore accepted.The field failure rate of the affected component is subject to continuous monitoring by the responsible prodcut quality board and is assessed as acceptable.
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