• FMC DISAGREE Message: Notes:
  • The FMC DISAGREE message shows when there is a data miscompare between the two Flight Management Computers (FMCs) in approach or on the ground. The message is amber in color.
    
    
  • If both the UNABLE REQD NAV PERF - RNP and FMC DISAGREE messages are active at the same time, they will show on two independent lines on the display.
    
    FMC DISAGREE Possible Causes:

    Before replacing any component perform FMCS Bite (Maint/FMCS/INFLT Faults).-Toggle FMC & control panel switch.

    
    

    1.Flight Management Computer (FMC)

    
    

    2.Toggle the FMC selector to BOTH on 1 then BOTH on 2, back to NORMAL.
    
    

    3.Wiring
    
    FMC DISAGREE Message:

    

    
    

    

    
    Circuit Breakers:

    FMCS CMPTR #1: P18-2 = E8 & A6.

    FMCS CMPTR #2: P6-1 = D16.

    
    
    Applicable deferrals MEL 34-36 Flight Management Computer System
    

Training Only