Machine Error 46 indicates that the ink absorber pad is full and needs replacing.  You will need an engineer to replace this.
If your machine is out of warranty, please contact Brother Customer Service from "Contact Us".

The ink absorbers hold liquid and dried ink after it has been purged from the print head. These absorbers can control enough ink for the expected life of the machine. 

Below are the explanations of how ink is processed into the ink absorber box. The Brother machine will automatically clean the print head when the conditions listed below occur:

• Initial installation of the ink cartridges:
  The Brother machine will perform an initial purge to fill up the ink tubes during the initial installation of the ink cartridges.
  
  
• While the machine is not being used, the machine will default to a sleep mode, which consumes very little energy.  When the machine is powered off, it cannot keep time of how long the power is off.  If you turn the machine off while it's not being used, when the power is turned back on, the machine will complete a cleaning cycle. 
   
• The first print job after a paper jam has been cleared:
  The Brother machine will automatically clean the print head to remove paper dust which can damage the print head if not cleaned.
  
  
• If the print head is not capped properly during the standby mode: 
  The print head will move to the right side and the purge unit will cap the print head to prevent air from drying out the nozzles.  If the head is not capped, the Brother machine will automatically clean the print head to clear out any dried ink from inside the print head.
  
  
• If the empty ink cartridge is replaced when the machine is powered off:
  The Brother machine will automatically clean the print head when the cartridge is installed and the machine is powered back on.
  
  
• If the machine is powered on, with no use for 45 day:
  The Brother machine will automatically clean the print head if to help prevent ink from drying and damaging the print head.