MFC-5840CN FAQs & Troubleshooting MFC-5840CN Not your product? Sort by: Updated Date Popularity 4 Results 1. 01/28/2013 The keys on the control panel do not respond. 2. 11/22/2011 My Brother machine has no power. What can I do? 3. 10/21/2010 How do I clear Machine Error 46? 4. 06/26/2007 Why does my computer become unresponsive when using the USB interface to connect the Brother machine? Others FAQs & Troubleshooting