Issue Observed: 

not sure if Someone may have plugged incorrect charger into unit, unit now does not work screen will flicker when connected to correct mains charge
 
Repair: 

Set up the unit to commence testing-unit was received with the main adaptor plugged in
Disassembled the unit
Checked over the mainboard where it connects to the charging port,
Found the DC to DC converter is faulty
An Alternator booster diode requires replacement
part is available in stock
After being replaced
Re assembled the unit
Recommenced testing
Unit is working
and no more faults are found