What was found
A/C RETURNED TO BLOCK FOR EQUIPMENT COOLING FAN 1 MSG. NO ETOPS OPERATION ALLOWED UNDER MEL 21-58-03A. SECOND WRITE UP FOR THIS. EA 06-475397-03 WAS ACCOMPLISHED IN SLC ON 8/8 TO INSTALL VIBE MONITOR ON FAN. FAN FAILED ON FIRST FLT FROM SLC FLT 2039/09. ATL REPLACED THE FAN. JFK MTC THEN REPLACED MONITOR AND FAN AFTER RTB. A/C THEN DEPARTED ON FLT 206 JFK-ZRH. TWO HOURS INTO FLT CREW ADVISED DISPATCH THAT EQUIP OVERHEAT LIGHT ILLUMINATED AND ALTN EQUIP COOLING SELECTED AND OVERHEAT LIGHT EXTINGUISHED. COMPLIED WITH EAV TO REMOVE FAN VIB MONITOR VA78743.