IN FLT 1.....Indicates CPU ALU internal test failure on the logic module.
IN FLT 2.....Indicates failure in the program PROM on the logic module.
IN FLT 3.....Indicates failure in the microprocessor internal RAM on the logic module.
IN FLT 4.....Indicates failure in the shared RAM on the interface module.
IN FLT 5.....Indicates a failure in the analog-to-digital converter circuit, on the logic module, used to convert front panel control values to digital values.
IN FLT 6.....Indicates that one of the two interrupts to the microprocessor (60 Hz weather or 453 label) has failed or does not exist.