The panel is displaying a MUX CPU FAIL. Is the panel or MUX Driver Card bad?
If the panel is wired Class A on the Multiplex Buss Check the Buss for a short - A short, ground or noise on the Class A loop will cause a CPU FAIL to be displayed on the Panel.
If there is not a short, ground or noise on the mux loop or the panel is wired Class B then do the following:
Power down the panel completely
Remove all MUX field wiring from the card
Remove the MUX Driver Card
Inspect the Pins and Socket for damage
Reseat the card Repower the panel - if the MUX CPU FAIL is still present, Try defaulting the panel -If the CPU fail is still present replace the panel and MUX Driver Card.
Part numbers FPD-7024, D7024, DS9400, DS9400I, DS9400M, DS9431, D7039, FPE-7039