Technical information
Technician’s Handbook
118
Flowchart 2: The System is Not Booting Up
Is the main 
controller card
numeric display 
flashing EE followed by 
an error code (2-digit 
number)?
Yes
C
No
No
Is the
main controller card 
numeric display 
continuously alternating 
codes B0 and B1?
Yes
Mass storage system is faulty. 
Check for faulty connections to the 
hard disks.
Power off the plane and then power 
it on again.
Next, try loading the system 
software from RSD. If you can’t load 
the software from RSD, see 
Removing and Replacing a Faulty 
Hard Disk on page 143.
Flowchart 2: 
System is not 
booting up
Reload the software (hold down the 
PANEL ENABLE button and press 
the RESET button of the affected 
plane). If the problem persists, 
replace the main controller card. 
See Replacing a Main Controller 
Card on page 147.
On redundant systems, set 
ACTIVITY FREEZE to “on”.










