Equipment cooling
Status messages concerning E/E cooling can often be cured by rotating the equipment cooling switch on the P5 panel to override and then back to NORM.
The E/E cooling air exhaust valve quite often sticks in closed pos. on ground, despite a modification program.
More:
There are four AC and four DC CBīs on the overhead panel for the flt control PSMīs (power supplies).
Pull all of them and push in the DCīs first, then the ACīs.
Great fix for status messages generated after overnight parking or after unwanted power interruption.
Take care,
Ballpoint. (15 years of -400 and still like them)