Troubleshooting 
 
FPΣ User's Manual 
266 
11.5  All LEDs are OFF 
If all LEDs are OFF, try the following: 
•  Check the power supply wiring. 
•  Check if the power supplied to the CPU is in the range of the rating. Be sure to check 
the fluctuation in the power supply. 
•  Disconnect the power supply wiring to the other devices if the power supplied to the 
CPU is shared with them. 
-  If the LEDs on the CPU turn on at this moment, increase the capacity of the power 
supply or prepare another power supply for other devices. 
-  Please contact your dealer for further information.