SOMETIMES BEFORE THE ERROR CODES 12 22 THE ERROR CODES 53 54 ARE DISPLAYED FIRST.THIS INDICATES THAT THE FANS ARE NOT FUNCTIONING BUT THIS IS NOT THE CASE.WHAT IS HAPPENING IS THAT THE POWER SUPPLY IS BEING SWITCHED OFF DUE TO OVER CURRENT AND THE FIRST ERROR'S TO BE RECORDED ARE THE FAN SUPPLIES DISSAPEARING AND THEN THE OTHER SUPPLIES.IN FACT I HAVE JUST HAD ONE IN THE WORKSHOP TODAY WHICH TURNED OUT TO BE FAILURE OF THE SCAN DRIVE I/C,S WHICH ARE PART OF THE PLASMA PANEL.WHEN YOU STRIP THE EQUIPMENT DOWN TO THE REVEAL THE PANEL IF YOU LOOK AT THE SCAN DRIVE I/C'S THEY USUALLY HAVE A LITTLE HOLES BURNT IN THEM THIS THEN BECOMES OBVIOUS WHERE THE ERROR IS BEING DEVELOPED.THE COST OF REPLACING THE PLASMA PANEL IS NOT WORTH IT. REGARDS DAVID