After just 146 A3 prints on the Brother J4120 the printer packed up with the absorbent pad full error.
Not a surprise really considering the number of head clean cycles it has undertaken. The pump on the Brothers really in not strong enough for sublimation ink.
Searched high and low for a solution on the internet but this model does not seem to have any answers to how to get around the problem. Here's a temporary solution if you have one of these printers - it might work with other brother printers with a touchscreen rather than manual buttons which has loads of solutions on the web.
This is the process:
Hold the home button down for about 5 seconds until the maintenance menu comes up.
Hold the bottom rectangle section down which is blank for about 5 seconds until the maintenance number pad appears.
then press *2864
this should show maintenance at the top left corner.
then press *80
this should show a number and letter code at the top. Use the >> button to go to the screen with up down cursers in the top left corner.
press the down curser quite a few times until you reach Purge
press 2783 this should reset the first purge setting back to 00000
you will then be back at maintenance so press *80 again and scroll through until the reach the SEN PURGE which is after the previous PURGE
press 2783 again and this should reset this purge to 0000 also.
press 99 to leave maintenance menu.
This is only a short term fix as you will get a notification that the absorbent pad is almost full but it will see you through for one or two more head clean cycles.
I can understand why the Brothers are not supported. I don't think the printers have the pump power to keep the head primed with thicker ink.
Hope it helps someone.