EICAS warning of "FWD EQUIP VAL".
Not much explanation here, but if the warning above is noted it is most likely that one of four valves is inoperative or has a bad position switch.
Inside the P50 panel is the Equipment Cooling Card.
Pins 7,9,10,11 should all have grounds with the aircraft in ground mode and equipment cooling in automatic.
If one ground is missing, it can be back-tracked to the faulty valve from the wiring or schematic prints.
767 WDM 21-58-12