public synchronized void collectFailingParts(WorkSheet sheet) {
        
        sheet.status = WorkSheet.Status.STARTED_TO_REPAIR;
        
        Mobile mobile = sheet.mobile;

        if (mobile.display.failing) {
            addPartToReplace(sheet, mobile.display);
        }
        if (mobile.keyboard != null && mobile.keyboard.failing) {
            addPartToReplace(sheet, mobile.keyboard);
        }
        if (mobile.microphone.failing) {
            addPartToReplace(sheet, mobile.microphone);
        }
        if (mobile.motherBoard.failing) {
            addPartToReplace(sheet, mobile.motherBoard);
        }
        if (mobile.powerSwitch.failing) {
            addPartToReplace(sheet, mobile.powerSwitch);
        }
        if (mobile.speaker.failing) {
            addPartToReplace(sheet, mobile.speaker);
        }
        if (mobile.volumeButtons.failing) {
            addPartToReplace(sheet, mobile.volumeButtons);
        }
    }